Hi,
There are some good B&B's in Playa del Carmen but most hotels in Cancun and the Yucatan in general offer only AI. We have stayed at the Iberostar AI Hotels in Playa Paraiso (Del Mar, Lindo and Maya) which are excellent. We have found that during day trips to Playa and Cancun it is very expensive to eat and drink out. May be worth considering AI; you would also have the benefit of more activities and entertainment for the children.

Cazz

It's not necessarily too expensive to eat out. It depends what you're looking for. When we were in PLaya a few weeks ago we were surprised at some of the reasonable prices offered for snacks such as chips, pizza and coke etc. I can't vouch for the posher restaurants but I'm sure we saw some that were quite reasonably priced.