Depends on where you live and the lifestyle you're going for;
But lets say you live in the South in a state with no extra income tax, then at 500k, you're looking at about 30k a month after taxes.
Just for funzies, lets say you save 30%, and now you're at 20k. Lets then say pay the minimum balance on your school loans, have no car payment, no significant other, kids, etc. That'll take about 5-7k a month out for loans and living and bills and property management.
So, after it is all said and done, you're looking at about 10k a month leftover for a hypothetical mortgage payment. (When I did the math for myself, it was more like 7 grand a month). So if you are going to pay 10k a month for a 30 year mortgage payment, then you end up with a 4 million dollar home-ish.
Not that the size of your house matters though, because it isn't going to make you a better doctor.