He said that he has to go back a number of years to determine any losses that were not allowed for NJ that can be added to basis...He stated that NJ does not allow net losses on rental properties ; however, those losses can get added to NJ basis so he said he has to go back and review all my losses over time.  

The area is growing like crazy and there simply is not enough housing.

Then determine if a long distance property is better or a local house hack.

You can also sell them on sites like paperstac, debexpert or others as well as brokers like Mission Capital, Rams or Phoenix.Depending on quality of paper and interest rate will determine sales price - also I would say self servicing can have a negative impact on the sales price as the major players in the space are not fond of self servicing. 

The loan amount will typically be determined by appraisal (LTV - loan to value ratio) - but your qualification will also be based on other metrics like you mentioned - DSCR ratio, FICO and some other factors. 

No risk, just reward—whether for personal deals, joint ventures, or simply passing along awesome prospects to each other, I’m always actively prospecting for new deals and sharing them with my network.Let’s collaborate, learn, and grow together!

Do you go direct-to-seller to find your deals or do you simply purchase from the MLS or wholesellers?

Assuming you meet real estate professional status (which it seems like you do - you'll just want to have a time log verifying) AND materially participate in your rentals, you simply wouldn't get that big of a year one benefit. 

One reason is the county is simply an agent for the State real property tax's are state funds then deligated back to the counties.

Water leaks, problems under the trailer ie insulation falling, a tub cracking, a new roof, frozen/cracked pipes (usually in January- and plumbing companies simply will not respond to mobile homes), rotting siding, bad exterior doors etc.