@Mark ********
some people have not needed this, but i just talked to a Russian man who with his family recently entered Thailand on a tourist and he needed to provide proof of accomodation for 60 days. he said if you write 90 days then they reject the hotels contract as the the tourist visa is technically only for 60 days and so including your extension in the duration is not accepted! From my weeks of research it seems that one must be prepared for everything as it really depends of which officer you get.