I bought a basic tool kit (sockets, pliers, crimpers, screw drivers, etc..) that also included some electrical and a tote. Every time I need a tool for the camper that I don't have, I buy it and put it in the tote when done.
Also a basic tool kit for truck.
Things added:
2 Air compressors (120vac 2 gal, 100#) and a 12vdc (150#)for the pickup.
Pop rivet gun (fix lawn chairs)
Tool to cut PVC pipe (made cloths line to hang on ladder for swim suits)
Electric drill and assorted bits
Bottle jack
Battery charger
Extension cords
Box of assorted fuses and light bulbs. If I need one I buy extras and stick them in the box for later.
Bow tree saw and hatchet
My tote is getting full but you get the basic idea. I can buy tools for "what if" but then I'd have way more tools than I might ever need. At least this way I can justify the expense.