It will depend on:
Availability - There may not be "points" rooms available for the time you want to go. The "cash" inventory is separate from the "points" inventory. However, there have been reports that guides can help arrange exactly what you would like to do, so be sure to ask.
Paperwork - If you are buying from Disney, all the papers would have to be signed (and financing approved, etc. if you are financing via Disney) before you can use your points to make a reservation. If you are purchasing a resale, I believe the sale must actually be closed before you can use the points.
State of residence - Some states are not yet approved for purchase of VWL via phone & mail. You could do HH or VB via phone & mail, or travel to FL to make the purchase of VWL (or VB or HH). If you are purchasing a resale, it won't matter where you live (I think! LOL).
If I have given you any misinformation, someone will be sure to let us know. Good Luck.
