To put it another way, for the amount you'll spend doing it up you couldn't buy one in that good a condition - new galv chassis, galv bulkhead - they don't come from the factory that future-proof. Yes in resale value terms you won't make your money back, but in lifespan terms you will. In satisfaction, skills learned and pride in the vehicle it will pay off tenfold.
And money spent on tools is never wasted.
Miketomcat built his tomcat under a mate's carport, goes to show what's possible (although he's not really normal for a number of reasons )