With that many people have you looked into renting a vacation home? We're a family of 6 and since doing it once we'd never go back to a hotel room again. A couple of good sites to check are www.vacationhomes.com and www.vacationrentals.com. For about the same price as a hotel you can rent a 3-4 bdrm vacation home with a private pool.
If you are including kids in your count, just get a regular room anywhere with 2 beds and put a kid on the floor with an air mattress or many hotels will rent you a cot. If all 5 are adults, you probably need 2 rooms.