My answer won't be, and for two reasons.

I don’t know what the costs would be to “scale” from the volume you do now to a volume you’re targeting, but it’s probably a reasonable investment.  

I am doing my best to accommodate and fix the insulation as well as see if there are programs in place to lower the cost. however i want to be firm with tenant as they are not compliant with paying rent because of the cost of the utilities.

Every market will vary due to labor costs. 

Everyone built 10 x 20'sfor some reason and they did it at the south end of town where thezoning is easiest.

Get replacement cost hazard insurance along with an umbrella policy of at least $1M, probably double in your area.

Securing funding has been challenging, particularly because my business documents reflect low revenue from only one duplex, and I am currently between jobs.I have identified a reasonably priced piece of land and have saved a small portion of the funds from my duplex sale to invest in this venture.

The type of the neighborhoods where his properties were located didn't fit in with my plan but he did well and the purchase costs were low.

One month of vacancy has cost you $2,400.

The best market is likely a "Good" cash flow market that you have some ties to, in some way shape or form, or one that is a reasonable drive from where you live, if practical/possible.