I need to be in thaliand for 97 days. Im an american on a single entry tourist visa.

So my plan is to extend it once to 90 days, then after 90 days are up, then do a border run to cambodia which should give me another 15 days. Is that ok you guys think or is there some kinda limit on extending like this.

OK

As said fine - but the exit/return will not be an extension but a new visa exempt entry for 15 days. You can also obtain 7 days to exit country with a disapproved request for extension to immigration if you do not want to travel - cost would be the normal 1,900 baht fee.

As said fine - but the exit/return will not be an extension but a new visa exempt entry for 15 days. You can also obtain 7 days to exit country with a disapproved request for extension to immigration if you do not want to travel - cost would be the normal 1,900 baht fee.

Oh, you mean after the initial one month extension to 90 days, I can get another 7 day extension? Making the total time to 97 days?

Yes - although that extra 7 days is not an official extension but the time allowed to leave on a disapproved extension application - but in effect it provides you an extra 7 days.