I personally would not rent the condo on the website you listed. Here's why:
Its a hotmail email address - who uses hotmail anymore?
Christmas, T-giving rates are considerably lower than other windsor hills properties for that time of year. Seems like a lure to me
I would suggest using vrbo. I have used them many times and never had a problem. I just rented a 3BR condo in building 8 (the one closest to the pool) for $89 a night. The balcony faces the pool too. Thats a good price for a WH property and the owners phone info is there, she has always emailed me promptly, and there are plenty of reviews. Sometimes vrbo owners also list their website and you can find more info. But I'd never start with a random website that had no vrbo connection. And through Home Away (also vrbo) you are protected on payments and it tells you how long they have been a member of the site.
If you are dead set on that condo, call the phone number and get the persons name and the condo #. Then call WH and see if you can verify that they own it.