Not going to get into legalities as in Thailand anything is possible with the right agent.
However, I would never, ever in a million years rent out my own property to someone else. People are animals and they will treat your "short term" rental very badly. If you want to get into this business, I would go the slumlord route. 4 walls, extremely cheap furniture and cheap rent. These units have a higher return on investment anyway.
I do rent out my own property back home, but only because I have no other choice. The government will slap penalties if the property is not occupied due to housing shortage and my insurance would not cover an empty unit. Also, condo fees and taxes are high. In Thailand everything is cheap. Imagine one of your short term tenants starts a fire here or damages the the treadmill in common area? Headache.