@Tim Swierczek the finished product can look like whatever you want it to, that is the beauty of new construction :)My thoughts are to keep things simple and instead of trying to re-create the wheel go off of what other people already have.  

There's no real 'fair' way to truly separately meter the natural gas used for the different units, unless you get into rabbit hole land of re-inventing a wheel and a series of sensors measuring heat and air flow within separate ducts, on your (customer) side.I'll comment on each option individually and your decision will be numbers driven. 

The chemicals were $400, and I essentially dug a 12 inch ditch all the way around the perimeter and dumped them in.

I installed a new hvac unit in my personal house, blew in 12 inches of insulation, added soffit vents 8 more of them, a ridge vent , and added storm windows at the recommendation of my hvac contractor. 

Like one little lot split i was doing in Lake Oswego.. we do the pre app and all the other things to get to a land use decisions ( probably 15 to 20k)  and no mention of this through the whole thing. .but one of the land use conditions was to replace the old water line in the street with a 200 ft run of 8 inch ductile iron.. all for hooking up two houses.. total BS this is a major road.. the cost to do this will be significant .. so we are appealing that condition.. 

These roofs are 3/4 inch thick , 6in wide planks .

Once you get her into court, you may have to wheel and deal with her in mediation or she may even lawyer up with a legal services attorney.

Oh yeah, we also renovated every square inch, including a new roof, HVAC, hot water heater, windows, waterproofed the basement, What was the outcome?

If you are trying to sell you are losing huge opportunity as you inch closer each day to the slower part of the year. 

As a wholesaler the majority of homes I found are more in a flippers wheel house so I was just wondering if anyone knew someone in the area who was interested in flipping!