check with your embassy/consulate. If you want to play games with immigration, it's totally up to you. Many countries get 60 days + 30. You could leave, and enter again for a further 60+30.....if Immigration officer will allow that
I do/did the same in Trat, Chiang Mai and Krabi!! Walk in, get a list of documents they need. Go home, prepare docs and head back to local immigration....no problems whatsoever. But it seems to be too much hassle for many people!!