And once you do buy, go back and compare to your estimates to actuals and adjust as needed.

My first filter would be comparing the cap rate of the property [this is basically the operating margin of the asset] with your weighted average interest rate [ for example if you borrow $80k @ 3% and $20k @ 9% your effective interest rate is 5%] If your effective interest rate is higher than your Cap Rate, the investment doesn't make sense, at least in the short term.

Compared to an IRA, Solo 401k contribution limits are about ten times higher.

It's a blue collar area with comparatively little appreciation but good rental cash flow.

We don’t know any PMCs to recommend in the area mentioned, but since selecting the wrong PMC is usually more harmful than selecting a bad tenant, you might want to read our series about “How to Screen a PMC Better than a Tenant”:https://www.biggerpockets.com/member-blogs/3094/91877-how-to-screen-a-pmc-better-than-a-tenant-part-1-services-and-processesWe recommend you get management contracts from several PMCs and compare the services they cover and, more importantly, what they each DO NOT cover.

How does that vacant unit compare in sq footage to the other units?

@Allen McGlashing, looking around, gross rents for comparables is around $60K

We don’t know any PMCs to recommend in the area mentioned, but since selecting the wrong PMC is usually more harmful than selecting a bad tenant, you might want to read our series about “How to Screen a PMC Better than a Tenant”:https://www.biggerpockets.com/member-blogs/3094/91877-how-to-screen-a-pmc-better-than-a-tenant-part-1-services-and-processesWe recommend you get management contracts from several PMCs and compare the services they cover and, more importantly, what they each DO NOT cover.

@Steve Adler Since it’s more than 4 units the deal we would base the deal on the numbers instead of comparable’s.

They will figure a average cost per sq ft around your local area, and then compare your house to those.