It's quite easy to do that find good companies and do good work in a very particular niche that underpromise and overdeliver (and go under on pricing) and use that to get more work at other companies. Then progressively go higher on pricing and do more than 1 (so you end up at 400k+) then pick the one you want and drop the other work. But if you start high you'll have a hard time proving your work easily, especially if its not specialised and you're not recognised in any way. It's alot of hard work to do the multiple at a go but you get there in the end.

If you simply want the $250k because thats what others are getting or something but cannot actually create the value you'll have a hard time getting there. An easy test for this is you feel you are underpaid at $250k vs being in a situation now where you can't get $250k at any job (non remote or otherwise)