Quote from @Jinglei Shen: Seller is a real estate agent, based in Ohio, he owns an LLC to flip house and invest in RE, this property is owned by this LLC. 

So, if you were a 'new' investor, but with your current skillset and knowledge base, and had $750,000 in net sales proceeds from a recent downleg property sale, where would you recommend investing in multifamily real estate? 

Mold for example could be in either category and if you denied a tenancy based on this and somebody decided it was a defect in the unit you could be in trouble.     4)  Another issue is if applicant has roommates they are NOT bringing along to your unit,   and those roommates caused whatever conditions in the existing unit.   

Im not an expert on title stuff, but I would not feel comfortable moving forward with the purchase if I was in your shoes based on what youve described.

For example:CapEx: $250-300 per unit per year for older properties, adjusted based on age and condition.Maintenance: $500-800 per unit per year, depending on property class and tenant turnover.Make-Ready Costs: $1,000-2,000 per unit for turnover, depending on the scope of work required.Resources and Tools: Utilize tools like BiggerPockets’ Pro Calculator or other underwriting spreadsheets that have built-in assumptions for these categories.

An additional benefit of a detailed engineering-based Cost Segregation Study is that it can increase potential insurance premium savings as well as provide support for the property tax appeals process.

What kind of database should I use to keep track of my leads and client base?

Then, more advanced stuff that those without licenses will have a tough time with: active real estate agents working the area - so i can call them to preview my house - in case they run into potential buyers they know of in their office, Then, I have Listingbook software on my I-phone ( Works with MLS data- by subscription)- that actually knows the number of searches of homes in any given area - so I can blast a promotion of my house to all the agents that have clients looking in the area (not just my subdivision -unless that is what I want), and...for the investor in me: track all the mortgages recorded against the property, so I know how low of an offer I can make - based on the mortgages on the property.

Based on the growth in that area, I suspect I will be able to refinance within the 5 year window and not require any cash into the deal. 

@Chris Pratt Since single-family houses with ADUs are not considered commercial properties, they are not priced based on income or cap rate.