My goal would be to build an investment net with passive income, de-risking the fact that I am the only earner.  

Because in reality, as soon as they exercise the option, I can redeploy that capital into another under valued asset and build wealth quicker.  

With that in mind, I’m considering purchasing four rental units over the next four years to build a stream of income that could help supplement my retirement by age 68.The challenge I’m facing is that the deals I’ve come across so far don’t make financial sense.

With your costs being less you can invest more into the property to build reviews and get bookings. 

@Albert Gallucci as many have pointed out, in the commercial space of 100+ apartment buildings and offices, property classes have some pretty decent industry standards.We started applying these to 1-4 unit properties around 10 years ago, which you can verify on our blogs, because we saw too many newbie investors not properly taking into account things like, neighborhood status, tenant pool, property condition, etc.Unfortunately, there's no industry standard for this, but you can use some basic logic to think your way through your own Classifications.

Building a cabin in a tourist destination that does not have easy access to gas or electric.So I will need to run electric line anyway and considering installing underground propane tank, is it worth it?

If you want good contractors out there quickly , pay their price and pay it quickly . 12 months is too long , we can build a 3000 sq ft house ground up in 3 months . 

I am considering working with a property developer in NJ to buy land, build a duplex/triplex and sell it (6-9 month time horizon).  

While I was running my inspection business, trying to build a real estate business, and taking care of 4 rentals with family, I was also going to night school to get a degree in MIS.

As for Cash flow, I think it depends on the deal structure as you mentioned, but also strategy/approach (cash flow vs building asset, holding long term).