Not sure this qualifies as the Swanage area, but here goes: A few years ago some friends and I stayed at a guest house in the Alum Chine area west of Bournemouth. It's called Fenn Lodge, at 11 Rosemount Road, postcode BH4 8HB. It seems to have been upscaled into suites since we were there but it's the same owners. When we asked them if there was a place to get an early breakfast, they set out items for a cold breakfast early for us. I'm not sure they still offer prepared breakfasts since the listing now mentions self catering, but that's how helpful they were for us. The area was quiet, not far from the beach, and the chine is host to foxes, badgers, and other wildlife. We were happy to avoid the Bournemouth stag & hen party scene! It was also convenient for our visit to the Jurassic Coast.