how much money would you have to spend to keep a rex runing right and in good condition

 

If you have to ask...then it is probably too much.

Depends on what condition the car is in to start with. If it just had its engine replaced, logical reliability mods with that, and was properly cared for...then just standard maintenance...oil, plugs, etc. Standard on a Rex is more than your average.

If the engine has not been maintained, then you guess how much it will take to care for it.