ok- some border points are famously more strict. Poi Pet, Cambodia for example. And some airports also tend to be more strict. BKK and DMK.
It’s quite possible you have no issues but definitely have the 3 proofs available. Onward ticket, 20k baht and hotel reservations to present to IO if you are questioned. You are more likely to be ‘warned’ and admitted entry. If so, you may need to look at border bounce with agency or FastTrack entry services afterwards
that’s the job of immigration officers. You weren’t familiar?
We can get questioned at any time. And how you respond to those questions will guide whether you get a seat on that bench or not. And producing the lease certainly didn’t help your case at all. So now u may expect to be a bit of a target
understood. Happens to some I think. If you show a contract though, you are essentially proving to them you are not there for tourism. Now, they know in your case and likely added a note to the file