I get a call from the same number on my cell phone every day: 888-226-3713. When I answer the call, the caller hangs up immediately.
I finally decided to call the number back from my work phone. A recorded announcement thanked me for calling back, and said that the call was from Bluegreen Resorts. The recording pitched some 3 day trip to Vegas.
I thought this sounded fishy, so I Googled "bluegreen resorts", and about the 3rd link was for The Ripoff Report.
I have no direct experience with Bluegreen Resorts, but I would say that in the very least, you should proceed with caution if you deal with them.
(Note: that number was 8882263713, Bluegreen resorts.)