Alegre Mar was recommended to us by friends who live i Mexico and it was an excellent choice. The apartments are right on the beach, with a patio and grassy area, beach chairs and shade, and water toys. An excelllent value.
The owner/host was available but not intrusive, and a great help at helping us find anything we needed in this great beach town.
LaManzanilla is a small village, but a tourism center for Mexicans, Canadians and folks from the US. If you want to explore any distance, a rental car is nice. But if you just want a beach front apartment, with plenty of places to eat out and things to do in the area, this works. Or you can do nothing at all and enjoy it.
This is not a RockResort, incidentally. If you want hot and cold running servants, look elsewhere. But for a really nice beachfront place to vacation, this can't be beat.