Should i buy it?
 

94 200k blazer 4.3 vortec. Started after sitting all winter first turn. Runs extremely rough almost stalling until you reach 30 mph then runs fine. A mechanic said needs butterfly valve(per seller) friend of mine thinks its a cracked fuel line. either way is this a reasonable fix?
Thanks alot

oh yeah left out the most important part. he wants $500

Depends on how much it costs. It's dangerous to buy a vehicle that already needs repairs. Bring the vehicle to your own mechanic if you have the chance.

Yeah, it also depends what they want for it, what features it has and etc.