for the application to the "change of visa type" from a tourist visa to a 90-days Non-Imm-O visa, the money just has to sit in the account. The 2-months seasoning is needed for the application to the 1-year Extension of Stay
one cannot get a 30 days extension on a 90-days Non-Imm-O visa. The only way to obtain 30 more days of stay permit, is to leave Thailand before the 90 days are up and re-enter visa-exempt
the TM30 is the registration of you in any accommodation, must be done by the hotel or the landlord within 24 hours of your arrival at the accommodation . . . . . .in case you were not asked for the receipt, you can call yourself double lucky!
Immigration generously granted an extension despite the overstay: they issued a 30 days touristic extension for 1900.- THB, however minus ONE day. And the 500.- THB overstay fine came on top of it . . . He's the lucky winner, now he is good until March 2nd
well you would have to spent the 1900.- THB on top of the 500.- THB by any means. On Immigration they might insist you take the 30 minus 1 -days extension OR the "application denied you have 7 days to leave the kingdom" stamp. Both will cost a 1900.- THB fee
you could visit Immigration and try to obtain the 30-days touristic extension you are eligible ONCE, with a visa-exempt entry. For the 1900.- THB fee, they might be willing to issue the extension minus one day. However I cannot guarantee this. They might also propose you leave the country ASAP and pay the overstay fine at the airport.