My father wants to use his SDIRA to provide a loan to the LLC him and I are equal partners in.The loan would provide the additional funds we require to purchase an investment property.The LLC would pay principle and interest at market rate to the SDIRA.Would this be considered a disqualified transaction? 

In advance: know what credit score, income, and equity are needed before you purchase to be able to achieve this every five years.

Getting prequalified for a loan is free (or should be) and usually is a soft credit check. 

I’m looking to purchase additional self storage mainly north east of Cincinnati but I’m open to location. 

We market the home, handle the showings, application, credit and background checks, verify income etc and then submit to the owner for approval.  

@Daniel UchimotoThere are some MTR specific sites in addition to Furnished Finders.

Are there any additional due diligence steps we should be doing before submitting an offer? 

@Kevin Barbot   the rental should be priced for the additional on property structures.

Another neighbor told me she offered them an additional trashcan but they refused. 

All investors should consider private money lending as an additional income stream if due diligence is done correctly and the project is a good fit.