Could signing a 1-year (!) condo rental agreement eventually end up giving problems (maybe being renewed for some years), if you’re in Thailand only on & off on a METV for approximately 5 months per year (maybe subletting it when not in Thailand)?
Would "the authorities" begin to think, that you are in Thailand all year around (I guess, your passport stamps would be proof, that you’re not...), and at some point deny entry because of this?
Thanks in advance, and have a great weekend!
TLDR : Answer Summary
The consensus among commenters is that signing a 1-year condo rental agreement while being in Thailand part-time on a METV (Multiple Entry Tourist Visa) is unlikely to cause any issues with immigration. Most immigration officers prioritize factors like entry history, proof of funds, and onward travel rather than the duration of your rental agreement. Some commenters noted that many people secure long-term rentals while only visiting a few times a year without complications. Subletting the unit may be more of an issue due to lease agreements rather than immigration concerns.