I agree, it does sound fishy to me... just like my caterer changing her mind on including the tables and chairs in the price and many other people that have gone back on their written word to me. It has not been a fun experience at all. Yes, I would be fine with the white plastic molded chairs, and I've told Susan that. She has told me that she did know of some pastic chairs that were cheaper, but she has told me several times that they were cracked and very bad shape and I would not want them for my wedding... even after I have told her several times I do not want to pay $10 for each chair or $400 for 40. I could buy a plastic chair for $10 each in the US, let alone rent one.
Did you get a contract on anything and put down money on it when you were first quoted the prices? Things do go up in price and I know it is hard to get some items on the island. You probably have to figure in it costs them money to transport the tables and chairs and have workers they have to pay to set it up and take it back. As far as you paying $10 for a chair in the US many things in Belize are much MORE expensive than in the US! They have to import items. You will see! Good luck.