Yes, you should be fine on 50k THB/mo. It's difficult and mostly meaningless to come up with an "average spending" amount. Depends on your age, background, habits and exact location. For a single Western expat in Bangkok, 30k THB is probably the bare minimum, and 50k is just fine. If you're from a low-income country, perhaps you can get by on a bit less. Where in Thailand will you be working? In Bangkok, I wouldn't expect to save much with 50k THB/mo. Important warning: beware of jobs nominally advertised from Thailand which might take you anywhere near a border of neighboring countries. They are often a front for scam call centers run by the Chinese mafia where foreign employees are held against their will. A "remote SEO job" in Thailand raises red flags. Why wouldn't you work for that same company from wherever you are now? Will they provide you with a Thai work permit and visa extensions? More on reddit.com

I’d suggest a shorter stay so that you’d have enough money to do and see something while you’re in Thailand. After hostel and food, you’d hardly have enough to take public transportation each day. You couldn’t enter any sites, get a massage, or travel to any other location without busting your budget. US700 is roughly 24,000 baht or 800 per day for a month. Ouch. More on reddit.com