Is a small investment in agriculture or real estate enough for a visa?

Would buying an apartment, renovate it and sell/rent it count as investment? Or getting farmland, tractor and grow potatoes? I'm not that interested in english teaching or office jobs.

The main reasons I wish to relocate to Mongolia is because it's too hot in Cambodia and not enough space to run around. It's really depressing when all what I do on a sunny day is close the windows and turn on aircon because just standing makes me sweaty. My body is supercharged to go through winter weather.
There are also plenty of snakes. Don't know if marmots bite but the cobra that I saw while running does kill. I have never had so much running energy than on that day. There is running space but very limited. The local mentality is to park oversized cars or extend homebusiness onto the sidewalk and hop on a scooter to go somewhere and then you see tourists walking in the gutter at +35C. It's very unpleasant and in two years I haven't been able to lose excess body fat. I used to have high blood pressure and now I have gallstones, so I want to live somewhere healthier. At least I can burn off fat at -35C.

I know Mongolia isn't better but compared with Cambodia, it sounds and looks much better (except for the winter pollution). I'll still do a visit first, maybe small cities suit my running lifestyle. So how do people get a long term visa if they open a restaurant in UB? Can't I do the same with agriculture or real estate? What I do now is build a house by western standards. Spoiled barang doesn't like showering next to a toilet with water flowing all over the floor. We put shower glass in between and then we sell it, mainly to russian families looking for a holiday house. But it's not a fast market, so I want to fiddle with agriculture too for some regular income.

Usually visas are given to those who invest half a million but what I have is a small, private, self-employed WORK. I don't even call it business. It's just work to me. It's easy to get a cambodian visa - $300 and valid passport (they don't ask for business documents), but I have never applied for a visa that requires proper documentation. Is there a way to obtain a visa without working for a company? Or can a mongolian national sponsor me if I get a land lease from them or however it works? Just wondering. I don't know yet if I can open a company with a mongolian national to own land. I'm still researching.

Any answer is appreciated, even the harsh one just like the harsh mongolian winter. I miss wearing jackets,  hoodies and long pants. But for now I'll have some fresh khmer coffee and plan the next trip to the cool mountains.
Many thanks