I keep the following parts in my cars:

1) good used AMM
2) power stage
3) fuel system relay
4) radio suppression relay
5) idle air valve
6) OD relay
7) 4 way flasher
8) fuse selection
9) bulb selection

For fluids:
1) minimum 1 quart of oil and transmission fluid
2) windshield washer fluid

Tools:
Just the tools to install 1-7 above-- in the 940 the factory toolkit does it all. I do have a 12V test light in one car and need to get one for the other.

I get all the parts from the local pick-and-pull-- 1-9 cost less than a single in-town tow here in the Greater Toronto Area.

Good luck!