I can't confirm that this applies to all kits, but certainly the one at the starting garage.

I also had this. The kit was still there after 4 uses.

I also noticed this bug. Usually it happens if you have a repair kit used 2 times, and you put it in the trunk. When you save and enter the game after, this kit will work not 3 but 4 times. There is also a bug with a fuel canister. If you put an empty canister in the trunk, after saving and loading it will become full.
--- Update ---
After you driven into Turkey, and Uncle is gone - there is no more free gaz in canister. Seems - it's like feature, Uncle awake everyday earlier, and buy some gaz for you, if you have canisters in car. And one more thing, with Uncle, if you haven't money to next motel, he rise up 60 marks for you at starting from home.