I stayed there for two nights while travelling with my girlfriend, and from the beginning the experience was a bit strange. As we checked in they asked for a passport (a common procedure in many places), but I was surprised when they said that they would keep it until check-out time, even though we had payed in advance for two nights. At that point I informed them that we were going to be leaving early in the morning of our departure, so we were informed that we could do the check out on the previous night. Mexico being a country with frequent military road controls, having personal documentation on you is a priority, but as it was the end of our trip and we were planning to simply relax on the beach for a couple of days we didn't give it any consideration.
Further problems started when later on that day I went to purchase a bottle of water at the bar. After being handed over a warm bottle I asked about its price, to which they replied "what's your room number?" I informed them that my room number was 20 and repeated my question regarding the price, to which they replied that it would be noted on my room's tab. I tried to pay for it there and then, but they said that it wasn't possible. I then said that at least I wanted to know how much I was going to be charged for it and after some grunting from the barman he said it would be 20 pesos.
Later on that night we went to have dinner at the restaurant. To say that the waiter was unfriendly would be an understatement and on top of that they seemed to have run out of everything on the menu. After a number of attempts at ordering we settled for some pasta , a chicken and mango salad a beer and a coke. 30 minutes after having placed our order the waiter returned informing us that they had ran out of mango too. At this point my girlfriend informed him that she would just have the drink. Another 30 mins later my pasta came and to our surprise so did the salad with mango and everything!
After finishing our meal we asked for a written note of the price of the meal to keep track of our expenses (again we weren't aloud to pay for it there and then). 45 mins later we got our note and we went back to our room deciding not to eat there again.
The night before our departure we went to settle our bill and recover my passport and we were told that the person in charge of check-out wasn't available. I informed them that we had to leave early the following morning and that I needed my passport back. The guy then said that check out was supposed to be at 11am! after further arguing we were told to return in an hour to see if the person in charge was available then. My frustration was growing at this point. My girlfriend then asked them to at least let us know how much we owed. One guy picked up this notebook and after fidgeting with a calculator he informed us that we owed 350 pesos plus a 10% service charge. Through our own calculations we knew that our debt was about 160 pesos, so my girlfriend informed them about this and said that the service charge was excessive bearing in mind the appalling quality of the service. At this stage another member of staff appeared and said that we were making him nervous and that he got violent when that happened. Luckily, I'm of a calmed and peaceful nature, so I ignored the comment and try to settle the argument with the other member of staff. The "violent" guy then started to say that he was getting increasingly nervous. At this point the person in charge of check-out magically appeared. We informed him of what was happening while the other two members of staff disappeared. He then gave us our proper bill which we settled, but when it came to get my passport back he said that he would return it at the time of departure. Again we told him that we were leaving early to which he replied that he would be there at our departure time. Not trusting anyone at the establishment anymore, I insisted, to which he replied that I would only get my passport once we returned the padlock (an old rusty one) and key for the cabaña. We had our own padlock, so I went to fetch their one . Funnily enough as I was returning their padlock, another couple were having exactly the same argument that we had just gone through!
I then got my passport which was kept in an easily accessible plastic box together with all the other guests passports, not the ideal place to store important documents.
Needless to say that when we left in the morning there wasn't a single member of staff in sight.
To give credit where credit is due, I must say that the toilets were very clean, but every other aspect of our stay there was a nightmare.
I hope that this saves fellow travellers from a similar experience.

I had read negative comments elsewhere about this place and it is good to see your feedback here. It is odd how there are good things mentioned here and there as well, but generally not by travelers. Do a google search for - Papaya Playa Shmaya - for similar experiences there. Do it soon, because that place often does not keep messages long.