Ground mount vs Roof mount?

Like Vinney wrote, it has many meanings. The way I learned it from my days of peddling process equipment and systems before switching to engineering was that it referred to equipment and services that were needed to operate a system that were not part necessarily described in the actual quote such as nuts, bolts wires, small accessories, startup incidentals, manuals etc. and stuff which, if added to a detailed quotation for the work would make it long and probably unwieldy.

The PN2000 Plug-in Kilowatt Electricity Usage Monitor appears to
be an upograde from the KILL-A-WATT. Competition.

1000 BTU/hour = 0.293071 KW, so generating 6000 BTU/hour with
your old style electric resistance space heater would require 1.76 KW.
With a Coefficient Of Performance of 4, your mini split would only
require 440 watts! The mini COP will decrease with colder weather,
but it will almost always be a lot better than 1 for your old space heater.
My minis were picked in part for their outside below zero performance.

Almost all the electric energy used by a mini split comes out on the hot
side. That to your benefit when heating. But it will not help when doing
air conditioning, so the COP might drop from 4 to 3. Normally the fossil
fuel energy unit costs less than an electric unit of that energy, but the
COP brings it back into competition. Moreso if you generate it yourself
with solar.

If you managed to run on 8KWh a day not including your mini splits,
you are doing very well. I barely managed 10, trying very hard.

It appears you are doing very well in controling energy use. But your
property is difficult for erecting effective solar panels. Is north at the
top of the picture? Yes I have an acre mostly dedicated to solar panels,
cannot be seen from a house or road. Perhaps you will not be able to
generate all your energy that way. Bruce Roe