I would also keep all interior doors open so you can draw the most moisture out as possible.

The issues with expansion and moisture issues cause tons of problems according to him

Perhaps your tenants can get their animals to piss where the soil is dry, so it will be more moist such that it will absorb moisture when S/he hoses down the area.

I don't like hardwood flooring in rentals because: 1) They are expensive to buy and expensive to install; 2) They require maintenance; 3) Re-finishing floors is also expensive and extensive; 4) They are not water proof/temperature proof and will buckle/warp if there is excess moisture from a leak etc. ; 5) Pets may leave gauges in the flooring from nails; 6) Compared to LVP they do not add any more $ in value LVP is nice because: 1) It's less expensive and easy to install; 2) Is water proof and scratch proof; 3) The thicker wear layered planks i.e. 12mil or higher will last longer than hardwoods unscathed; 4) its pet proof; 5) In the off chance that many years down the line there is wear on the floor, you can replace them still for cheaper than you can refinish hardwood flooring, and its a new floor again. 

The cardboard will kill everything under it and prevent weeds from growing and the mulch will help keep the moisture in the soil.My tenants are responsible for maintaining the yard and most do a good job. 

When the source of water intrusion is known, and the spread of moisture is measurable and its known that the biological growth is spreading from the source across an affected area - what is the point of testing what is already known?

Bottom line: If you keep it under 60% its just not enough for mold to grow.You are in Sad Diego, that's a lot dryer than Milwaukee (we run a dehumidifier in most basements) so if you find more than 60% you definitely need to look where the moisture comes from!

Stachybotrys Chartarum will grow readily on the unseen paper backing of drywall, ceiling tile, paper moisture barriers, wallpaper, and other paper or wood products, especially in bath and shower areas where constant moisture is present.

There is moisture in the ground, there is moisture IN the concrete, and, depending on your preference, the pool itself may be left full (or nearly) over winter.

-Walls 2 coats of sheen of your choice-Trim 2 coats of Oil Base Enamel SemiGloss$1,750 labor only$2,300 material provided (Sherwin Williams) and touch up paint left for your property-Repairs:Material cost estimate $60-100(Labor Only)Plumbing repairs and tie in - $400Minor Carpentry - $100Wire bathroom switch - $50Repair broken window - $50-Floor Repair/Level/Floor Installation:Labor for subfloor, caulking cracks in foundation, laying moisture barrier, and installing underlayment and laminate$2,400Remove existing flooring and subfloor and rafters.Lay moisture barrier and seal house of leaking cracksInstall and level new rafters 2x10 pressure treated, and install 3/4" subfloor.Lay laminate underlayment and install laminate to match surround floor height.