I understand the preventive measure is in the buying stage.

Here's a copy and paste from their site on how it's calculated:The FHFA HPI is a broad measure of the movement of single-family house prices.

Should we take extra measures when having our properties cleaned between guests?

If I did have a short term rental (we are in the market for one, hence the trip) I think I would post the additional cleaning and sanitation measures that are being implemented to ensure cleanliness of the rental in between renters.

Purchase price and down payment are negotiable, at least to a certain extent.Cash on cash is a great measure, but is heavily influenced by the financing. 

The statewide rent control measure, AB1482, does allow you to increase the rent, if you do major renovation.

You make a phone call, they come out and measure, provide a written quote.

It measures 9'x5' at widest points and is 17" deep.

I was given access to a set of building plans including basic measurements. 

I appreciate your close attention to maintaining safety of the property and will advise you of the decision made by my insurance and contractor regarding appropriate measures.