They pay their own electric, and you're right, after reading a bit about mini splits, even low ambient systems look like they might struggle on the coldest nights.

For speed & convenience I only use the premixed mastic & grout as depending on ambient temperature the mixed powder stuff has been a big problem.

Owners trying to rehab themselves often don't know little tricks such as adding a spoonful of dish soap to their mud to help eliminate air bubbles (and thereby, an additional coat), or that the process of coalescence in exterior paint is negatively affected by an ambient and/ or surface temperature below 50 degrees.Being from Cleveland, unfortunately I can't much help with the Milwaukee area.

With regards to heating from the heat pump, if you are concerned, as your contractor for a unit with low ambient capabilities. 

As for mold, the indoor air was actually cleaner than the ambient outdoor air (how does that happen?).  

- Add under-cabinet lighting for a functional and ambient touch.Inspiration: - Opt for pendant lights to create a focal point

I now know that there's a certain ambient level of anxiety involved in living in an apartment, particularly a basement/ground-level apartment.

A mobile has virtually no wall bay thickness, no attic (slows transfer of ambient temp) and under a mobile is very poorly insulated.

If you have water lines in an outside wall, and the unit is reaching ambient temps, that cold air will travel and freeze the pipes all the way up to the top.

This time in my life makes me like Jazz, Ambient and New Age types of music.