If it's a V6 than you need to check out the head gasket. If possible grab the VIN off the thing and go into a toyota dealer and see if the head gasket has been replaced under the recall yet or not (toyota will do it once). If it hasn't than you still have a "get out of jail free card" when the headgasket does go. Even if Toyota did the head gasket already it still could be blown. Take it to a mechanic if you aren't sure and have them check it. You could be looking at $2000 if the head gasket is going on it.
Also, if it's the 3L V6 than it will be slow, especially if it's an automatic.
Check to see if the tailgate window works.
If it's the 22re 4 cylinder than you should be good. It's a very realiable engine. The most common problem with those is the timing chain. You might hear a rattle at low RPM if the timing chain is due for replacement. If it does need replacing don't get a cheap timing kit. Get one that has metal guides. You can buy them online from engnbldr.com for a good price
I've owned both a 4 cylinder and V6 and I would definitely buy another 4 cylinder but not the V6. I don't trust the head gaskets on the V6 and to me the 4 cylinder felt quicker around town. The V6 seems to haul a trailer better though.