How can we accurately perform a market analysis to ensure we are investing in the correct locations?

Due to the inherent characteristic of this type of siding to deteriorate if not properly maintained and the difficulty in detecting all damaged areas, a qualified siding installer should perform a more in-depth evaluation.

The whole idea is to get in "light" - with as little cash out as possible.Purchase price: $80Kdownpayment: 20% ($16K)seller gives you $30K rehab creditCash at closing: $14KOwner 1st mortgage: $64K, interest only, 8% ($426.67/mo)Maybe negotiate to refi in 2 years or 1 year with a one time extension of 12 months with a 1-year advance on mortgage payment ($5,120).With that mortgage payment, and if you can indeed rent both units at $825/mo or $1650/mo total, you will cashflow from the deal even with the 50% rule.I would suggest though that you put the deed in escrow to be sure the owner does not walk out on you and get your downpayment and a renovated property at your expense.

Cash flow is only one metric of performance of an investment.

A home inspection will find foundation problems, extensive roof damage, and mold.

California now has a pretty onerous brightline test of sorts after the Dynamex case last year in the CA supreme court.A hired worker will be considered to be an employee unless it can be shown the worker passes ALL of the following test:1) The worker is free from the directions and control of the hirer in connection with the performance of the work, both under the contract for the work and in fact;2) The worker performs work that is outside the usual course of the hiring entity's business; and 3) The worker is customarily engaged in an independently established trade, occupation, or business of the same nature as the worked performed for the hiring entity.Note this is a lot more restrictive than the federal "questionnaire" for an employee vs IC determination. 

Performing as expected as a long term hold Lessons learned?

He did not perform appropriate due-diligence on these and/or maybe fell into the high-income Dr. mindset of "money is an easily renewable resource". 

To paraphrase this idea - your outsourced accounting partner should by performing the work and proactively providing solutions, as opposed to giving you items to research.

@Charles Kao Yes they have signed leases till next 5 years so no need to renegotiate the rents... couple of Tenants have extensions after 5 yrs term...