Ask dog-owning friends in your area for recommendations. Avoid anything that provokes remarks like "well...we had to bath him / her when we got him / her back.

I know a good one in Northumberland, and several not so good ones we tried before we found the good one.
As to costs, expect around 10-12 pounds a day. There's usually a discount for several dogs.

If your dog came from a breeder it could be that they would house it for you.

Good luck
Paws