Modern lifestyle seems to start at $700-$800 per month per adult pretty much everywhere and doesn't get much better even at few k.

It depends. In a ridiculously cheap country like India where food prices are hilariously low you can get quite far on $200/month. Fresh vegetables (tomatoes, potatoes, onion, garlic, spinach, squashes, gourds, eggplants etc) are literally an order of magnitude cheaper than what you would find in a cheap American grocery store. You can also get full meals from restaurants for about 30-40c. Medical care is also dirt cheap with most regular doctor visits costing between $1-$2. High end medical care and surgeries for less than $1000 for the whole procedure and stay. The PPP multiplier is something like 6-7x.