Not sure what year models you're considering, but here are a couple of things you might want to consider and look for.
The early model V6 Tacomas had a defective
"head gasket" and from what I understand... it was a pretty costly fix, because the whole top half of the engine (the head) had to come off to replace the defective gasket. There was a recall issued to
"fix" the problem, which was... a VERY GOOD thing. I've actually gotten 2 seperate recalls on my '95 Tacoma, but to date... mine has shown NO SIGNS of this being a problem and... my truck now has... almost 128K on it!

I bought the truck with 40K on it... about 5 years ago now, but... the fact is... it's been...
ONE HELL OF A GREAT TRUCK!

That said... I'm a FIRM believer in...
"if it ain't broke... don't fix it".
Also... it's my understanding... that the later model Tacomas (i.e. 98-04, I think)... had some kind of issue with the tailgate rubbing somewhere on the body. Matter of fact... there are still auctions on
ebay, which offer a
"fix" for this. Check it out...
http://cgi.ebay.com/ebaymotors/ws/eB...928440508&rd=1
That's really... all "I" know of! Isn't Toyota... just a great truck... in general?!
Good luck in your search...