Booking and Staying in Hotels
Unless you are going somewhere between Christmas and New Year, want to see Antigua, Guatemala, during Semana Santa, or you will arrive late in the "Maya Riviera" during high season, especially between January and February, you probably won't need a reservation. There are other exceptions, but if you feel that you must reserve to make someone with you happy or you are set on staying at a particular hotel, you would do well to do so only for the first night. If you book for longer, you could be surprised by what late night noises may abound, including barking dogs all night or roosters that will not await the dawn. Good luck getting your money back.
When you enter a hotel, don't presume that there isn't a room that will go for less than the posted rate. There may be a less desirable one a bit close to the laundry room or a bit small that you can get for less.
In general, when there you should always ask to see the room before paying. Check it over closely unless you are really tired and don't care. If you think it is overpriced, often asking to see something "más económico" can produce a similar or even identical, but less expensive room. It has for me. If you don't exactly like the room, saying so could get you a better one if there are any to be had. My favorite example of this was in downtown Cancun near the bus station, where I looked at a room that looked depressing, mentioned that and asked if there was a better one. There was and it was not only much more cheery; it also had a balcony overlooking the quiet residential street for the same price.
Don't presume that just because the hotel door is solid and has a good lock, that all is well. Someone with a spare or master key could get in. When sleeping, I like to place something in front of the door that will make a lot of noise if someone starts to come in. Empty bottles and cans work well, but other things do as well.
When I go out for the day, I like to leave the most important portions of my pack locked up. Most crimes in hotels and many other places seem to be ones of stealth. Any would-be perpetrator will probably want you to be well away before you realize that something is missing from your luggage. If it were sliced open, you will obviously notice right away.
More Maya Area Hotel Advice, which is not from me, but it is good.