Holiday Lettings has continued to be disappointing and as other reviewers, owners and guests have said, the booking fees are extortionate.
Have a look at a new(ish) site 'theholidaylet', I think they are worth supporting while they build up their straightforward ad service. I've now also listed with Airbnb, HomeAway and Owners Direct. The last two are affiliates - if you list with one, you'll be offered a deal for the other. And they have 'sales' when they reduce the fees. I initially took the free listing and have now taken subscription - OD has produced more results.