The IRS has said, since 2017, that the improvement ratio or $ value is what your taxes are assessed as, unless you have a really compelling reason to use a different value. 

Do I consider it as an SFH and assess potential rental income based on SFH?

Also, there's the added risk of being compliant with federal regulations & state laws as well as properly assessing/vetting both the borrower and the property.

Didn't mean to get political but I generally vote no on anything that will cause more rent control or increase my property taxes (all the special assessments).  

Otherwise every vacant lot would be assessed to have a multistory building on it.

I have heard it’s cooled down quite a bit and assessing if it’s still a worthwhile option to consider as a market for str or even mtr? 

I understand that that a home in Jerome Village would already have property tax, that would include additional fees for the roads, infrastructure, etc. and that it's based upon "millage" and the home's assessed value. 

Underwriting will assess the performance and appraisal of the property based on traditional long-term rental comps.

This could mean investing in property flips or purchasing out-of-state rentals for more stable income, but it would require letting go of the $1,350 rental income from the manufactured home.What factors should I consider for each option, and how would an experienced investor assess this situation mathematically?

For example, you buy a house for $1,000,000 but you say you bought it for $100,000How do they find out how much you paid for a house to assess their tax?