Hardwood is beautiful but expensive and easy to scratch and is finicky around moisture and humidity. 

Is there a reliable method/way to maintain a constant moisture level year-round so as to protect the foundation from shifting that would compromise all of the extensive renovations that have taken place?

If the installer has to go around a corner, force the lines through a tight (or blind) penetration, or just isn't careful; they can kink or break the lines which leads to a host of problems that won't be covered under the mfg warranty.They don't heat enclosed bedrooms or bathrooms really well when the doors are closed.

Penetration pricing - get traction with early bookings at low prices, gain credibility with 5 star reviews, and improve pricing / profitability from there.5.

Any moisture trapped will just cause mold.If the cracks are small or hairline cracks you can most likely go over the existing grout with no issues.Where the tub meets the wall there should be no grout EVER.

@Johnathan Williams, the most value is added with roof repairs, mold remediation and water penetration causing mold, flooring and siding repair that are CLEARLY rotten and would CLEARLY depress the price if sold "as is," complete rewiring if the electrical is old enough, and hvac repair but not upgrade.

Low spot is about 1/2" lower than a high spot.We also found that the puddles form in the crawlspace when it rains, and it's very likely the flooring sagging due to structural damage from the moisture.

This basically seals the building envelope from the inside, taking care of any little leaks and penetrations in the building.Fine Homebuilding and Green Building Adviser have done a ton on mini-splits (they love them).

About $6K to replace the HVAC itself.Give the mold, you might eventually need the air ducts cleaned.Do the bathrooms have vents to get rid of excess moisture during showers/baths?

but to just stick them in there and never check.your going to have filters never changed and maybe ruin your HVAC.. your going to have water leaks that cause dry rot..your probably going to have plumbing issues.. you have a tiny leak in the roof and next thing you know mold behind the walls.you catch them putting sheets in the window or even worse  Aluminum foil which creates moisture and moisture damage and mold.I can go on and on.. this is the benefit of self managing.. and if your not.. then pay your PM to stay on top of these folks. its money well spent.. both for peace of mind and your pocket book long term.My A class new construction that rented at 1400 to 1700 which was the very tippy top of the market..