“The whole kit and caboodle” is an older expression for what we might nowadays say is “the whole nine yards”—that is, “everything.”
 
In the 1800s, the phrase was variously given as “the whole kit” or “the whole caboodle” or “the whole kit and biling” or “the whole kit and boodle,” among many other variations.
 
“Kit” is an old Dutch word meaning a wooden vessel made of hoop staves. “Caboodle” or “boodle” is an old Dutch word meaning possessions.
 
“The whole kit and boodle” appears in print by at least 1849.
   
   
Old West Writer’s Guide
The whole kit and caboodle ~ the entire thing.
     
Dave Wilton’s Word Origins
Kit and Caboodle
Kit and caboodle is everything, the entire of collection of things under consideration. But it’s an odd-sounding phrase to the modern ear. Kit doesn’t seem to make much sense here and what the heck is a caboodle?

The word kit is from the Middle Dutch kitte, a wooden vessel made of hooped staves. This original sense of kit remained current in English at least through the 19th century. It appears in English as early as 1375 in Barbour’s The Bruce:

“Thai strak his hed of, and syne it Thai haf gert salt in-till a kyt And send it in-till Ingland.”
 
The earliest known use to mean a collection of items is from 1785 in Grose’s Classical Dictionary of the Vulgar Tongue, which glosses kit as:

“The kit is likewise the whole of a soldier’s necessities, the contents of his knapsack: and is used also to express the whole of different commodities; as, Here, take the whole kit, i.e. take all.”
 
Caboodle is a variant of boodle, which means a number of items or people. It comes from the Dutch boedel, meaning estate, inheritance, or possessions. The term in the original Dutch sense was introduced into American English as early as 1699 as this citation from that year in Lederer’s Colonial American English attests:

“Elisabeth had the Boedel of Jan Verbeck, desceased [sic], in hands.”
 
By the early 19th century, boodle was being used in the phrase the whole boodle to signify everything, the entire collection of something. The Journal of American Folklore records this usage from 1827:

“He . . . turnd out the hol boodle ov um.”
 
The form caboodle appears as early as 1848 in this citation from the Wisconsin Democrat, 16 December of that year from a Whig candidate who lost a supposedly safe seat in an election:
 
“It is no use to be a “Son,” it’s no use to be a whig, it’s no use to be nothin’,—I’ll cut the whole caboodle.”
 
The combined form appears by at least 1861, when the following is recorded in Theodore Winthrop’s John Brent:

“I motioned we shove the hul kit an boodle of the gamblers ashore on logs. ‘Twas kerried.”
 
And by 5 February 1888 the Boston Globe was reporting:

“If any ‘railroad lobbyist’ cast reflections on his character he would wipe out the whole kit and caboodle of them.”
 
So kit and caboodle is a redundancy. Both elements of the phrase mean roughly the same thing. Such redundancies are common in English.
 
World Wide Words
WHOLE KIT AND KABOODLE
 
[Q] From Elma Brooks: “What is the source of the whole kit and kaboodle?”
 
[A] Caboodle has a complicated history. It’s been spelt down the years in many different ways, and these days is usually listed in dictionaries with an initial “c”. It means a collection of objects, sometimes of people. It commonly turns up in the whole caboodle, meaning “the whole lot”. It’s recorded in the US from the middle of the nineteenth century. It’s probable that the word was originally boodle, with the phrase being the whole kit and boodle, but that the initial sound “k” was added to boodle for euphony.
 
There are examples of similar phrases around the beginning of the nineteenth century, such as whole kit and boiling (or whole kit and bilin’) and whole kit and cargo, with the original very likely to have just been the whole kit—it’s recorded in this form in Grose’s Dictionary of the Vulgar Tongue in 1785. It was also current in the US as the whole boodle from the 1830s. It seems that the whole kit and caboodle eventually won the linguistic battle for survival in the US because of that repeated “k” sound, though Dialect Notes in 1908 said that these other versions were still known from various parts of the country. Sinclair Lewis used one of them in Main Street in 1920: “The whole kit and bilin’ of ’em are nothing in God’s world but socialism in disguise”.
 
Boodle is familiar as the relatively modern US word for money illegally obtained, particularly linked to bribery and corruption. This is usually suggested as coming from the Dutch boedel, “inheritance, household effects; possessions”. But it’s uncertain whether it’s the same word as the one in the whole kit and boodle. Some writers suggest the latter comes from the English buddle, meaning a bundle or bunch (closely connected with bindle, as in the North American bindlestiff for a tramp). As kit here means one’s equipment, to put the two together in the sense of everything that one has, equipment and personal possessions, seems reasonable.
 
(Oxford English Dictionary)
caboodle
slang (orig. U.S.).
[Supposed to be a corruption of the phrase kit and boodle (see KIT n.1).] 
the whole caboodle: the whole lot (of persons or things).
a1848 Ohio State Jrnl. (Bartlett, Add.), The whole caboodle will act upon the recommendation of the Ohio Sun. 1873 B. HARTE Fiddletown 3 She had more soul than the whole caboodle of them put together.
   
kit, n.
[app. a. MDu. kitte a wooden vessel made of hooped staves (Du. kit tankard): ulterior etymology uncertain.]
colloq. A number of things or persons viewed as a whole; a set, lot, collection; esp. in phr. the whole kit. Also, the whole kit and boiling (boodle, caboodle, cargo). (Cf. CABOODLE.) U.S.
1785 GROSE Dict. Vulg. T., Kit,..is also used to express the whole of different commodities; as, Here, take the whole kit; i.e. take all. 1788 R. GALLOWAY Poems 170 (Jam.) ‘Twas whiskey made them a’ sae crouse;..But now I wad na gi’e ae louse For a’ the kit. 1821 SHELLEY dipus Tyr. I. 92 I’ll sell you in a lump The whole kit of them. a1852 F. M. WHITCHER Widow Bedott Papers (1856) xxiii. 257 The hull kit and cargo on ‘em had conspired together. 1859 BARTLETT Dict. Amer. (ed. 2) 32 Biling, a vulgar pronunciation of boiling. The phrase the whole (or more commonly hull) kit and bilin, means the whole lot, applied to persons and things. 1861 DICKENS Gt. Expect. xl, A better gentleman than the whole kit on you put together. a1861 T. WINTHROP John Brent (1883) xxviii. 237, I motioned we shove the hul kit an boodle of the gamblers ashore on logs. ‘Twas kerried. 1888 Boston Globe 5 Feb. 1/3 If any ‘railroad lobbyist’ cast reflections on his character he would wipe out the whole kit and caboodle of them.
       
20 December 1843, Tioga Eagle (Wellsboro, PA), pg. 1, col. 6:
“Worry them out”—reckon he did, and told them to bring in any friend they had and he could cry out the whole kit and bilen of ‘em, and if that didn’t satisfy them, make them feel the points of his five knuckles besides.
   
13 February 1849, Huron Reflector (Norwalk, OH), pg. 1, col. 5:
Horace Greeley, when the whole kit and boodle of the honorable thieves in Congress turned against him as no gentleman, owned up in the following Ben Franklin style.
     
Wright American Fiction, 1851-1875
Eutaw, a sequel to The forayers, or, The raid of the dog-days
Simms, William Gilmore,
New York, Redfield, 1856.
Pg. 435:
“Ef he had but three fellows with him, and they had the we’pons, he could jest now scalp and massacree the whole kit and b’iling of ‘em.”
 
Making of America
Title: Putnam’s monthly magazine of American literature, science and art. / Volume 9, Issue 50
Publisher: G.P. Putnam & co. Publication Date: February 1857
City: New York
Pg. 196:
Mistress Beadle’s children were all bewitched, the whole kit and posse of them;...
           
Wright American Fiction, 1851-1875
New England’s chattels, or, Life in the northern poor-house
Elliot, Samuel H.
New York : H. Dayton, 1858.
Pg. 209:
The town paupers of Crampton, who aren’t worth, the whole kit and boodle of them, two bright cents in the world, come to me to ask if they shan’t put on a regular suit of crape!
     
Wright American Fiction, 1851-1875
Benedict, Frank Lee, (1834-1910): Miss Van Kortland (1870) 1 match in 1 of 178 pages
CHAPTER XXXVII.
ton said carelessly, but looking keenly at her. / “Don’t I tell you they’re talking about her, the whole kit and boodle of ‘em—things that would make your hair stand on end, wherever or how
   
Wright American Fiction, 1851-1875
Eggleston, Edward, (1837-1902): The Hoosier School-master (1871) 1 match in 1 of 227 pages
CHAPTER IV.
ough him. / “He’s powerful smart, is the master,” said old Jack to Mr. Pete Jones. “He’ll beat the whole kit and tuck of ‘em afore he’s through. I know’d he was smart. That’s the reason I tuck hi
     
Wright American Fiction, 1851-1875
Donaldson, James Lowry, (1814-1885): Sergeant Atkins (1871) 1 match in 1 of 323 pages
CHAPTER XI.
e strike-from-the-shoulder code. This handsome proposition being rejected, he scornfully denounced “the whole kit and caboodle as a set of sneaking, cowardly, breech-clouted niggers!” / Having th    
 
Making of America
Title: Americanisms; the English of the New world.
Author:  Schele De Vere, Maximilian, 1820-1898.
Publication Info: New York,: C. Scribner & company, 1872.
Collection: Making of America Books
Pg. 583:
Biling (instead of boiling), the whole kit and biling, an expressive phrase, heard in the West, to designate the totality of persons or things. “At one time there was good reason to fear that the whole kit and biling, as our men invariably called out traps, would be swept away, but by a great effort they kept the boat upright, and, although thoroughly drenched, we saved everything.” (A Trip to the Rocky Mountains, 1869.)
       
Making of America
Title: Wanderings of a vagabond. An autobiography. Ed. by John Morris [pseud.]
Author:  O’Connor, John.
Publication Info: New York,: The author, [1873]
Collection: Making of America Books
Pg. 94:
“He’s a thief, Mr. Lane, an all them fellers connected with him are a set of thieves, the whole kit and bilin’ of ‘em, as you’ll find out to your sorrow, if you trust any of ‘em!”
   
Wright American Fiction, 1851-1875
Coffin, Charles Carleton, (1823-1896): Caleb Krinkle (1875) 1 match in 1 of 507 pages
CHAPTER XLVI.
up any more if I’d tried. Coffeepots, skimmers, ladles, dish-pans, buckets, pails, tea-kettles, and the whole kit and boodle lying around promiscuous. Dan, you did well that time, but what are you goi