As already stated, other than the design element stated its the price as stated at market rate. That amount for the design element may fluctuate over years but the weight is the weight.
My 2 penneth, DONT ! I would rent. That gives you mobility if needed and bypasses all the pitfalls you are setting yourself up for.
Finally, dont spend 1 baht more than you are prepared to walk away from.
Good luck in your choices.
As with so many things here, I would say it depends entirely who you encounter on the day.
If you live here, yr ID card or driving licence can often help to show you are not a tourist. It had helped me several times (but not all).
I was kind of hoping your next post would be a job of some description.Dont worry about the negativity, people need to see the reality.
Hope you keep posting and things improve soon.