thank you so much! Was trying to get detail about visa application here at Thai Embassy Jakarta but couldn't reach them by any means, so i guess this is the best way for current situation.
okay in my case it was my second extension and my money went below 500K for 5-7 days. The officer saw it and marked the bank statement (asked "did you use the money?") but i didnt get any charges. In Chiangmai btw
the 500K deposit needs to be shown when you're about to extend to 1year stay. so basically 3months after you enter thailand. your max date to submit extension is the date shown on your passport.