That won't make a difference. If they think you're living in Thailand on a visa exempt entry, then you're toast. Even TVs don't allow multiple entry without issues.
It all depends on your nationality. Some nationals can get scrutinized even with a single TV entry in a year. As long as you are suspected of not being a tourist.
There are many hotels from budget to mid-range normally, that offer discounts at the front desk v online. It varies greatly and depends on the season, hotel etc.
There can of course be properties where the yield can be attractive. But we have to speak in general terms. Bangkok isn't known for high returns in the property market.