I think its always going to be tricky to make these sort of estimates. For comparison there is a big range of properties available at Polaris World
Polaris World - UK Sales and Reservations but prices are from 120K to 1.5 million Euros. The facilities are pretty good but rental returns vary. So much depends on how the property is furnished (needs to look inviting in the pictures) and how good the rental agent is at marketing.