I see you are from NJ, like myself, and @Natalie Schanne hit the first key point - you need to have a brokers licence on the business.

When we are handling rental income for 3rd parties, a licenced property manage brokerage must be used.

I will likely partner with/hire a licenced broker as it is a requirement here in NC.  

But with a Local , licenced and insured company you may be talking to the owner when a problem arises .

A Vendor selling her house or the bank-of-mom-and-dad, unless they are in the business of lending, do not need to hold a licence to lend to you.  

Get a copy of everyone drivers licences.

A DBA is just a fictitious name and really doesn't have anything to do with the structure of an entity, just the name (at least as far as I'm aware of). 

Here is a story for you, I have a tractor trailer rig to pull my race car and hotrods places, a CHP inspector told me that 90% of the people from his country that drive trucks come to America buy a simitruck and drive with no licence!

Hello If I don't have a real estate licence so what's the best site i can look to find maximum information about property...I know zillow as a great site but can't find everything there ....Please share your experience about property research.....thank you very much

While noble, on the surface, the attempt by the federal government to restore stability to the housing market by selling to primary residents is fictitious, by and large, at a time when mortgage loans are so difficult to procure.