In easy words, THERE IS NO LIMIT.
I have worked with coders with team who are now making around a million indian rupees in a month. In some cases, it takes more than 5 years to reach the same point while some reach this point within couple of years only. While some who start never earn.
So just take a leap of faith, and consider yourself to be successful one in upcoming years and start today. Work hard, very hard even when you don’t get any jobs, just keep working on proposals, profiles, in improving your skills and reading blogs and books to learn ‘How to sell your skills?’. And always respect your clients.
Hope this helps!