and ask them what carrier they prefer or wish they used for their area. the answer may not always be what you would have expected, so ask. never ask a carrier sales person themselves due to the fact that they are after your money. you might not get an honest reply.
there are many different types of phones out there, and who knows maybe a free phone is what will work best for you, however a little bit of research can go a long way. do a bit of digging and get the most for your money aka contract. 