We visited the RSPCA to enquire about rehoming a female puppy. The cost was £90 including vaccinations, identichipping and neutering. Will thay spay the pup before we take her or if she is too young will we have to pay for it at the vets when she is old enough ?

Think you need to ask the RSPCA about that, but would guess that they will ask you to take her back when she is old enough, well I would hope so anyway.