Maybe find out you didn't replace cathodes, and the water is harder there.

I wasn't sure if there was an "industry-standard" way to approach investors, luxury brokerages, etc. 

You should be calculating Cap Ex for all long term items that will need replacement at some point - appliances, roofs, ac, water heater, etc.

Hvac, Insinkerator, furnace, water heater, toilet, fiberglass tub, roof, driveway, etc...Here's a link: https://www.hud.gov/sites/documents/EUL_FOR_CNA_E_TOOL.PDF You might also want to consider a home inspection for each unit with a written report, and a sewer cam report.Good Luck!

The standard is your intent and  how you can demonstrate the intent of the property. 

You are subjected to regular section 8 inspections, but as a good landlord you'd want to keep your properties up to standard anyway.

I don't think it's worth it to me in the long run from past mistakes and I'm going to stick to my standards.

Tenant now requests a water softener (we live in a very hard water area) due to clothes not being clean, stains, etc.

Of the 3 cities, I am leaning towards Charleston since it is bounded at least partially by water and wetlands which would prevent large-scale urban sprawl and increased supply of housing.

Yes for houses directly on the water (such as the bay) and in a flood-zone.