Do you know if that is true with a raised foundation packed with R-30 insulation?

Make sure to address the condensation problem by insulating the walls or installing a dehumidifier.Good luck with it!

And while, to a degree those assets compete, they offer a different style of living, and thus are relatively insulated from volatility in apartment supply.

For thickness of insulation reasons, 2x6 studs against the outside wall would be best, or 2x4 studs and spray foam insulation (R=19 or 21) (R=13 in a 2x4 stud would be OK.)

Has anyone else solved this issue by using some sort of insulation you can put between the joists in the ceiling to minimize the footstep/moving around noises you inevitably hear daily? 

For 2018, you determine your basis for your rental house to depreciate it over the next 27.5 years by taking the lesser of the completed current appraised value (adjusted by building:land ratio) OR the cost of purchase, plus mortgage interest, home insurance, PMI, RE taxes, utilities, new roof, electrical/plumbing, appliances, drywall and their labor cost, insulation, doors/paint/trim, lawn service, and tool rentals, basically EVERYTHING I've spent up to the in service point, adjusted by building:land ratio. 

We learned fairly quickly that a home this age comes with a lot of liabilities, being badly insulated, more prone to animal infestations (palmetto bugs, bats, squirrels, etc).

I wouldn't do anything about duct work unless there is evidence of the insulation flaking, then it should be addressed.

.: Insulation, or lack thereof.Just ran into this one and it really surprised me, but I guess the transition from floor fan to window air conditioner to central air were all upgrades to a better way of living and that pesky outer wall insulation was an expense that just didnt make any sense back then.Energy efficiency???

Jacob, we no longer vent any crawlspaces, we insulate and encapsulate which leads to much fewer issues with mold and mildew.