if we choose sub contractors for each work and we manage all the work independantly then need to take insurance is that correct ? 

Marketing the education is optional, and I believe it is one of the most humane ways to compensate an independent business owner.

Have to know when to say no to someone. my Dad who taught me how to sell real estate and work with the buying public always told me Son your an independent contractor you choose who you work with not the other way around and the most important word is NEXT. 

You can learn to do this independently or get a rockstar REALTOR to lead the way.

I published an 11-part series on all about DSCR Loans here on BiggerPockets in case you haven't seen them yet - should be very helpful hopefully!

Along with Shannon, I recommend reading 30-Day Stay by Zeona McIntyre and Sarah Weaver, published by BiggerPockets.

If you want to reach financial independence, a good income + limited expenses will be the catalyst.

Take a look at BP's blog where new articles are published every day: https://www.biggerpockets.com/blog4.

The retirement/financial independence equation he uses is a paid off primary home, 500k in liquid assets (usually retirement, cash, and after tax brokerage account), and more than 1 source of income (part time job, real estate, social security for those of that age, dividends, etc.).

Take a look at BP's blog where new articles are published every day: https://www.biggerpockets.com/blog4.