Should I take a car to get checked / tuned up before a cross country road trip?

What would I tell the mechanics I wanted them to do? How much would just a look over type inspection cost? Should I leave out the fact that I basically want to know if anything needs fixing before the road trip because a number of mechanics will take advantage of that. Should I get it looked over by more than one mechanic place for second opinions and second set of eyes? I don't have a regular mechanic at this point. I also have AAA.