Generally,Location+SF+Amenities+Market Demand = Rent (in dollars).Now think of the right side of that equation as a scale.

I've been looking at out-of-state investments and have been very interested in SFR within a 30 minute drive of large military bases, specifically in Fayetteville near Ft.

You will also learn to appreciate when a real estate agent is actually doing their job correctly, vs the large number of agents who just show up and do the bare minimum.What prompted me to take the course was that my first agent was not very good, but I couldn't actually truly assess and understand that without knowing myself, now I can confidently say that she wasn't very good, (lucky me, lol).Short Answer: There's not a glaring reason I can think of to not educate yourself on it, even if just for education's sake.I can't provide info on the 2nd part as I'm just not as familiar with specific MA to CT reciprocity and requirements.

If the lot is in highly populated area, it might be a great deal, but if its in a rural area, it might just be too much effort for a large builder to just get 5 lots.

Wanting to trade up into larger buildings is effective all things being equal there are definitely economies of scale, and personal preferences too.

That skilled is used in every aspect of real estate investing ... if you plan on scaling ... 50 properties or more.

Honestly, it's too bad that the operating part of your dad's business does not carry with it some residual value of some sort with regards to that commanding a sale price.My hunch would be that this would be far too risky to embark on as a first go of things.Especially, from what you're mentioning this may have a large impact on the quality of your dad's retirement.If you have the funds and can structure something, the place to start would be to engage with an A/E firm to get a cost estimate generated for a concept building like you're mentioning. 

They are offering a large down payment and to payoff the loan within a year. 

Trying to think out of the box for some investor clients here in Sacramento (I am an agent) so I am looking for SFH with large enough properties and will plan to use him to build ADU's to make them duplexes, in theory. 

However, I am confident that I would be able to successfully generate buyer and seller leads at scale using Google/Facebook/Instagram ads, so I am tempted.I've also thought about using my marketing experience to get leads for distressed properties and then wholesale them, but again I'm a newbie when it comes to investing in real estate, so I don't even know if that's practical in my area (Seattle).Are there any other paths I could take that comes to mind?