But what if I am getting paid salary from a source in India? In other words, it may be that in India a research assistant at a college on average earns a third of what a research assistant like me earns here in US. In that case, even if my cost of living there is much less, so is my salary.
This question although closed as economics, can equally be closed as Broad or Opinion based.
It's not just salaries, there are sites that provide a good guidance for what the average salary for an profession with x years of experience would be. This doesn't solve the issue.
Purchasing Power Parity is also know in quite a few currency pairs.
There are various aspects of lifestyle that are different. Hence comparison for like to like becomes difficult ... hence broad, and what to adjust to becomes opinion ...
A relevant example my friend in US had a Independent Bungalow in US. It was with Basement and attic, 2 levels of living space with 4 bedroom. He shifted to India and got a great salary compared to normal Indian salary. However this kind of house in India in Bangalore would be affordable only to CEO's of top companies. So is living in a 3 room apartment fine? There are multiple such aspects.
Drinking a Starbucks coffee couple of times a day is routine for quite a few in US. In India this would be considered luxury.
When I was in US, I couldn't afford a maid, driver or any help. In India I have 2 maids, a cooking maid and a driver. Plus I get plumber, electrician, window cleaner, and all the help without costing me much. Things that I absolutely can't dream in US.
Plus there is traffic, cleanliness, climate, culture, etc ...
All these aspects are very different.
A research assistant in India is poorly paid, because colleges don't have funds. Research in fundamental science is quite low. Industry to university linkages are primitive and now where close to what we have in US.