cheaper to buy one already done but then where the pride and joy in that you get to say "yeah i bought it from so and so pretty bad ass hey" and who's to say the guy built it right or knew what he was doing ive ran into a situation where a guy told me he had it in his vette it was a 3970010 4 bolt 350 i was gonna rebuilt it any way come to find out he had a push rod chilling in the lifter valley and enough gasket sealer to fill up a 5 gallon bucket
i prefer to build um myself then when some on compliments you can say "I built that" sure it cost more and take more time but thats the way i would go not let some other joe schmo build it for me
-J.M.O