1st Generation Tundras

I'm interested in one, they seem to be a decent compromise in size, cost, etc. How many miles am I looking at out of a Tundra that's listed for $10k (might be able to talk him down to under $9k), and has 130k miles on it (this is the primary vehicle I'm pursuing, 2002 SR5 V8 Access cab)? Can I expect 200-300k out of the truck?
Whatever I select as a vehicle, I want to do new suspension, tires, etc. and make an Expo rig, but the truck needs to be able to come home and be a utility vehicle during the week, and a Tacoma isn't able to haul enough/simply isn't big enough for the loads I need to deal with.
I'd go for a second generation Tacoma, but they're too small and really expensive for what you get, and a second gen Tundra just seems too big/gas-hogging, and I'm more scared of working on such an expensive vehicle (I want to do the work myself).
To get a Tacoma the capacity I need (for work, not expo type stuff) I'd need to build a flat bed and then tack on suspension, tires, etc. It seems like the initial cost savings and lack of need to build a flatbed would offset cost of gas to feed the Tundra, unless the older truck is going to be exorbitantly expensive to fuel/maintain, or if the engine/transmission is 50k from dying where it is.
Am I way wrong? Will the Tacoma save me enough gas to be worth forking over what could be $8-$10k more, given the cost of building the flatbed?

 

Nothing??