Christmas vacation for family - possible purchase of timeshare

My wife, her parents, and my 3 kids all went to the Cozumel Palace last Christmas and loved it. We are looking to do this again, but are trying to see if there's cheaper options out there without going to Costco Travel. We felt like we got a decent deal last year but now my wife and I are considering listening to a timeshare pitch. We love going to Mexico and we live in Houston.

I'm open to suggestions. Is it cheaper to purchase someone's timeshare, and locate a flight?

Hi Palace Resorts are not really a timeshare. They sell certificates which can be redeemed for one week stays at members rates. Members rates vary according to when you bought in, what type of membership you bought etc.