I have been twice this year, going back again September, stay two weeks at a time, never had any problems, always have return ticket but never been asked for proof of return ticket.
£920 pounds monthly pension is nowhere enough to retire in Thailand. by the time you paid rent, health insurance, energy you might just have enough left for food to survive.
I have been twice this year visa exemption, always stay two weeks at a hotel, will be coming back twice more this year staying two weeks at a time. Never been asked a question or delayed by immigration.