Depending on what state you're in, you may need a real estate broker's license to start and operate a management company.

If an investor has the time, knowledge, capital and experience to be an active property investor then there are a number of strategies , that, depending on the economic market can be used to accelerate wealth building.  

@Michael Whitman , it would totally depend on the company, but you make a great point.

Yes, depends on if he already has a loan and the rate on that. 

(Usually you cannot use prior employer history until you have been at your new job for 6 to 12 months, depending on the underwriter to show that you are maintaining the same level of bonus/overtime/commission income that you had at your prior employer).

Whether it still makes sense will depend on how much you can defer vs. the basis.

I find it's very personal, and dependent a lot on your goals, resources, risk tolerance, location, experience, etc.

It depends on the rental income, what you plan on putting down (20-25% is typical, 15% or 25% is required for conventional depending on # of units) For your owner occupied deal, you should be able to use a portion of the rental income to qualify and help offset your DTI a bit. 

Alexander,It depends and varies hugely.

Depending on the situation, a taxpayer could offset some of the passive losses with active income.