I know you are joking but there have been reports of people on overstay being arrested at Phuket airport departures before they could exit. You are no longer safe, it seems, by making it to the airport.
The 800k is tied up for 5-6 months from 2 months prior to the application for the first 12 month extension then 400k for the rest of that extension while the 65k monthly deposits run in parallel "from the beginning"
You register an account with the landlord's details (tabian baan & Thai ID) but your contact details. You then have full control of the account at login with Username and Password. Once registered you add the address and the final stage is to add the foreigner details and arrival.