Yep, lots of colleges take AP credits. In general, publics and non-elite colleges are more generous, the more selective the college, the less generous, and top LACs are the least generous (capping the most).
As for study-abroad, at many schools, you pay whatever you would have paid on campus. This is much more true with privates, it seems. I know that at UIUC, you pay the cost of the study-abroad program, which are all over the place, with some costing more than OOS tuition and some (especially the exchanges) costing less than in-state tuition.