This was relatively painless to sign up for. The only issue is the pulldowns for the district and subdistrict didn't fill when done in English. Province worked just fine, but the others wouldn't trigger in English even with just single letters. So I just did the address in Thai. But afterwards it shows the address in English for the places that were pulldowns. The street in in Thai since that is manually typed.
It seems to be a 2 step process. Set up what is probably a user account. That login info came almost instantly. Then go back to your Profile and add any addresses that you're responsible for.
I think this cuts out massive amounts of logins since the old system required identifying as the owner, manager, tenant, etc. So I think a property manager had to register each place with a separate login. At minimum, if they managed, rented, and owned different locations, those would be separate logins. A renter now seems to be able to keep the same account, then add any new places they rent, and can delete the old. Same for owners, who may also be renters or own more than one place. Just add any addresses regardless of who you are relative to that address.
I could be wrong about that, but I recall the registration being address specific, rather than person/entity specific before. They didn't ask for the title document for my condo, only the house book and id/passport. They should probably add a check box for each address where you specify that you are the landlord, property manager, renter, etc.