Siam Legal can help if in bkk area. Isaan lawyers if you are going to be near Korat ( Nakhon Ratchasima). if Mom is getting SS check monthly do account at Bangkok Bank if u are form the states. Are you?
You have to apply on line then get a permission letter sent to you. In the airport next to the Immigration lines, you will pay a small fee and get in the que. they will call you and issue then u go to the immigration lines next to it
I also stayed on Soi 11 at the Holiday Inn Express. 42,000thb. Almost the same review as Abid. Room and bathrooms were nice. Really comfortable bed and pillows (a must for me) good tv, no balcony but nice relaxing area on the roof to go to each day after first test. The staff was awesome, always at my beckon call and bent over backwards to accommodate. They all made the stay much more bearable. I would recommend it!
There are generic samples on the internet. Check Thaiest. They are 1 page documents that a doctor had to fill out saying you have no serious infectious diseases and need an escort or wheelchair assistance or serious medications. check Dr Donna as previously mentioned. I just got out of quarantine and best to get from your own doctor w their signature, letterhead and doctors number. They wanted it upon entry.