you will need to show that you are leaving and entering again again to show the need for a multiple entry visa. I'm not sure if that has to be within 60 days or the 90 days, but you must show an exit ticket and a second entry ticket to show the need for a multiple entry visa. So definitely not the total amount of days. Again, you'll need to show at least 2 entry tickets and 1 departure. The good thing is, you can get close to 9 moths stay from this visa
I think in order to get the METV you need to show you leaving Thailand and re entering. This shows the need for a Multiple entry. You can always use an onward ticket company for the application.
does the ip want to live in thailand or does he want to visit a number times as a tourist? I think that's my point, a tourist visa is a proper visa for that purpose.
spends like the OP wants to visit Thailand multiple tomes as a tourist, I couldn't see where they want to live there. 🤷♂️ I used to go 4 times a year, others go more times. All on either tourist visa (real visa) or visa exempt (no visa)