what to to

I got 2 questions.

First, on a 1/2 ton truck what is considered to be alot of miles?

Second, would it be better to buy a new truck with less miles on it for more money or buying an older truck with alot more mile but for alot cheaper? My thinking is that if i get an older one with more miles I will be able to put the money i save into the truck to swap the engine and do any other work it might need. ANy suggestions?

i would get a newer, used one .. for an average price with good miles and get the best of both worlds..