There are some ads on this page! You are often better trying to rent them in the country you are going to. You won't get charged the exhorbitant rates in the 'high season' here. Florida's high season for example runs from Dec - Apr.
I've been with James villas a couple of times to Tenerife, not too expensive but check price flights before you book, you can get cheaper on the web.
Do all the bits yourself, it works out cheaper, flight, car hire, insurance