I have two, two-binned caddies from Target and a medium-small, single bin, open top plastic box. I use one caddy for towels, the other for bottles. I use the box for cleaning related tools and other supplies. I keep all three in the trunk. Fortunately, the trunk is large, so there is a lot of room remaining.
Towel dimensions are approximations.
Towels (In Caddy 1):
3-4 6"x12," Platinum ("PLT') or Canning Vale ("CV") rectangles -- for QDing
4-5 3x12, PLT or CV strips -- for spot cleaning, Bird bomb or mud splash removal
2-3 12x18 PLT or CV rectangles -- for extensive QDing, or spot drying in case the car gets wet.
1 30x 40, PLT or CV -- usually used for drying, in case of rain, to forstall water spotting.
1 30x40, Charisma, Burgandy colored towel -- for special occassion use, to give the car a quick onceover to remove any white lint left by the above towels; used every once in a while.
All the above towels have been trimmed of ornimentation and have been surged.
1- 12x12, medium plush mf towel for window cleaning
1- 12v12 suede mf for window drying
1- 12v12 plush mf for interior cleaning
The MF towels are trimmed of labels.
Cleaning Liquids (in Caddy 2)
1 Spray Bottle, each, of:
Distilled Water -- for 1. window cleaning directly -- i.e. without a window cleaning solution; 2. as a rinse spray after using a window cleaning solution; or 3. to rinse paint after spot cleaning with Z7.
Beverly Hills Motoring Assessories Window Cleaner-- (used only on tough matter, such as dried bugs)
Z6 -- for QDing.
Pre-mixed Z7 -- Generally, only used on items that do not remove with the Z6, or which I know will need extra cleaning help to loosen; the few, rare times I do not catch a Bird Bomb early (using Z6), I will soak it in Z7 prior to removal if there is any question that it has dried, in order to reduce the chance of paint damage from wipeing off the BB.
Zaino Leather Cleaner -- For use in case of spills or soilings.
In the Box:
Cal Duster - has not been used for five months
Hand-sized carpet sweeper
Box of Swizzles
In the lower compartment of the console in the cabin (i.e., inside the car)
Small spray bottle of distilled water
Small, plush MF towel
1 Swizzle
All the above three items are for spot cleaning or dusting the cabin.