The entry fees are correct on our website. You can confirm this on the government website here: http://www.yucatan.travel/es/rutas-turisticas/ruta-puuc/
The entry fee includes admission to the site and the obligatory guide into the caves. THEY DO NOT HAVE SET FEES FOR THEIR GUIDE SERVICES, IT IS BY TIP. However, what has happened, is that many visitors do not appreciate their expertise and leave them either no tip or a meagre one, so they are trying to protect themselves. This is their only income. (It is not a perfect system, but that is the way it is.) If a guide approaches you and asks for an "official" or "obligatory" fee, you should go to an official on the site and report it. Get the guide's name and take a picture if you can, and send it to us, we will report it, we want to help prevent this type of scam. My advice would be to negotiate an acceptable guide service fee before you enter the caves; and that fee IS your tip. In my opinion, 450 or 500 or 600 pesos is too high. I would pay 200 pesos for a family of four. Good luck.