Never had anyone wake me up before and a simple NO Thank You should suffice. Most of the vendors will remember that u said NO and respect that.
Also most hotels on the beach have security, if a vendor won't take NO for an answer let your security guard know. At the Treehouse, Moses has came to my rescue a few times.
There are some annoying characters who keep bugging you but they are the minority.
The Majority of vendors are just trying to make a living. If you don't want to be hassled in their country maybe you are better off at an AI.
I've been to Mexico a few times and can remember being hassled by children selling chicklets gum ALL Day!!!!
Resort towns are all the same, tourists=revenue.....Don't go to a touristy town?????
Oh yea even walking down the street in NYC's touristy areas you get hassled to buy anything!! I got hassled a few months ago by street vendors selling cds the guy wouldn't take no thank you for an answer even after I said I don't own a cd player !!!