Several Factors
I did not understand the title of your post �If you had to start over�.
You asked
And play bj as your primary source of income how much would you need as your bankroll? Or if you have a job and play part time how much would u need to quit? For me I think I would need to have 150k-200k and always have 200 or 150 top bets. I don't think you can make your money grow any faster in any other business but I don't know how many times a year you can double your bankroll after a couple years betting at that level.
It sounds like you are asking about Solo play. There are very few people who actually support themselves on a reasonable income as a solo BJ player. Most people who are doing this for income play as part of a team.
Part of the answer depends on your financial situation. Do you have another source of income, such as a spouse who had a day job and benefits? Or maybe you have a retirement pension? Or are you plan on having this as your sole source of income ?
What kind of a job are your leaving? If your at a low level job at Mc Donald�s, then you don�t have much to lose but quitting and trying something else. But if you have a better paying job, with benefits and with years of service, then I would advise you to think hard before quitting. In my case, if I quit my job to play full-time I would take a net reduction in overall income.
If you are playing BJ as your sole source of income, you cannot take all your winnings as income. You have to re-invest some of them back in the bank, to build up a cushion against a losing streak. Otherwise your RoR becomes 100%. There is an excellent post in the GC archives on this point.
In this situation, you should probably play at the quarter Kelly level. Move about half your income into the Bank, and pay yourself the other half.
You will average about 1 Kelly Equivalent Bank for each N0 that you play. If you get 4 N0 a year, you would make your bank each year. For example: if you bank is 100K. You could play to a KEB of 25K, which is heavy green / light black. (At this level, you will have to a LOT of comp hustling to keep down your expenses). If you got 4N0 of play, you would earn 100K a year. You could put 50K in the bank, and then take the other 50K as income. This is your income before expenses, before paying self-employment tax, and before medical benefits.
To get 1 N0 of play you, you could play 200 hours with a SCORE of 50, or 100 hours with a SCORE of 100. Getting 4 N0 a year from full-time play may sound pretty easy to someone starting out, and you may do it in your first year or two. But your hours will fall in each year as you lose more and more casinos. I know full-time players who don�t get many more hours in a year than I do.