Sellers indicated they did not care about closing date/cash offer so we decided to skip on it and not tie up large amount.

Once you're deemed credit worthy by lenders you can start using leverage which needs to be used VERY carefully but is also extremely powerful.I personally do NOT recommend that someone with a trades or self employment 'life track' as you are describing is best suited to buy a first house with cash, and for instance use your time to fix it up.Few reasons here:Firstly, often the kinds of 'cash deals' available are ones that can to generalize tend to be more cash flow type properties (as opposed to equity properties). 

Careful.. you may want to gets some books at the library and do some reading first. 

I would rather drive for 3 hrs than have to fly & pay for a hotel for a few days to take care of issues & then fly back. 

Use conventional financing to buy each 4-plex individually, but close them simultaneously.It is likely that the owner doesn't care what kind of financing you get, but their loan might be a tied loan, so untying them becomes more complicated. 

I always assume electricity, gas, water, sewage, trash, snow/lawn care, and wifi to be paid by tenant (except HOA). 

You'll have to determine how accurate these numbers are though, and I still don't see any utilities (unless that's billed back 100% or 100% paid by the tenants) or lawn care/snow, unless you don't have to worry about that based on the landscape of the building or built that into the repairs.

I really like my current apartment because it's well taken care of.

Millennials care most about the location and the proximity to amenities like parks, shopping centers, restaurants, nightlife, etc.

(Just fyi, this isn't an amazing neighborhood, probably B- so maybe tenants wouldn't care?)