I have two options 6.625% 30 year or 6.15% 15 yearI want to invest aggressively in the near future on more propertiesThe loan is only $110k and the monthly payment for 15 year is $563 and $750I will earn 2-3k a month in gross rental revenueThe property is in a declining population areaRecently rennovated, and all major things were relatively recently improved such as plumbing, the roof, a/c, electric, etc.Will require a lot of management as it is rent by the room so I may switch to a normal rental after 10 yearsI'm trying to find what will mathematically net me the most money in the long run.

For my money, I'd look there and let the market bring you up.

@Sung Yu the above posts are right on the money. 

That will determine if you could sell it and use the money to buy a single family home or would need to take out a mortgage. 

Normally, companies keep changing their name after losing all investor’s money.

It can be only for the reason that you got your money working for you instead of the other way around. 

Deal 1: 4 Plex (it's stripped down to studs, a guy ran out of money on the rehab)Purchase price 160k, Rehab 80k, Total all in: 240kExpected Rent: $4,000/month to $4,400/month depending on how quickly we want to rent the units out. 

Suggest you pester them with questions to learn the eviction process, so you can save money in the future.

Spend your time and money learning how to avoid that kind of situation rather than learning from on the job training.

Interesting idea, but I suspect that would create more problems than it is worth.Most of the leverage you have with a NNN lease is that you are working with a company, presumably one that makes money.