First off, check the building number if you are staying in a condo. The higher the number, thc closer the building is to the pool. Look at this resort map.
http://www.davh.com/WINDSOR HILLS RESORT MAP.htm
The condo buildings are numbered. Then, ask yourself if you want to be close to the clubhouse or not. If you go to bed early, the pool noise could keep you awake, although the weather in January may be too cold for outdoor swimming at night anyway.
Ask what is included. We got to our condo and found out we had to buy our own toilet paper (one roll per bathroom was all we got), our own paper towels, trash bags, dishwasher soap, and bath soap. We did get a blow dryer, ironing board & iron, and no extra charge for a crib, high chair (didn't need anyway), free phone and free long distance, and playstation w/ games.
Ask if there is an extra cleaning fee. Many of the owners will waive the fee if you stay at least 7 days. I think some of the owners are negotiable on their prices. We were able to get $10 less per night and no cleaning fee, so ask. All they can say is no. Many will say yes rather than risk an empty condo. The poor economy is hurting them, too.
Ask to see pictures of the actual condo you will be in. I found one owner who said they assign condos upon arrival and only provided stock photos of the resort itself. Not good enough for me.
Check on the cancellation fee. Many owners don't have one at all or the most you lose is 20% while others will take it all. Also, find out the method of payment. Some only take Paypal and want to charge you the paypal fee, but will let you mail a check to waive the fee. That means though that you have to have the money paid up front vs paying it off on a credit card.
And, as others have mentioned, if you feel that the owner is friendly and replies back to you in a timely manner, then thiink of that as well. If you can't get a hold of an owner and your A.C. (or heat in the winter) goes out, you will be miserable!
Good luck! I'm sure you'll find something wonderful.