Mold needs moisture, the right temperature and food to grow.

Thank goodness here in Georgia we don't have the freezing temperatures you have.

So far, I’m thinking about extra closets with locks, maximum number of bedrooms feasible (aiming for four or five), fireplace and some kind of a nice outdoor deck or screen porch, possibly a hot tub.

Currently, I have a full time job in the fenestration business, and I was legitimately curious if the whole concept of "indoor/outdoor living" had a major effect on home values in the Phoenix market.

Quick & consistent rental history as leases usually end in summer; prospective tenants enjoy outdoor seating/patio area Lessons learned?

You can also add wifi lights and thermostat, allowing you to control the lights and temperature at a distance.Only allow them to enter the premises in your absence after they email you a photo of their driver's license and if it is more than one person, get photos of all of their driver's licenses.

They have some outdoor space also. 

I'd put some outdoor type of tiles, but use whatever is appropriate aesthetically.2. 

The historic main streets are filled with restaurants, outdoor cafes, shops, galleries, and other pedestrian friendly locations, mostly brick roads with pretty elevation changes. 

Upstairs tenants currently have no way to regulate the temperature of their unit, and this is Minnesota where we get to -20 degrees in the winter...