Anyone can be a QI so make sure the organizations you interview have safeguards in place like insurance, bonding, experience, expertise, etc.

But if you are buying an older home, the key person to interview is the maintenance manager.

Find 3-4 you like, interview them, pick 2 you really like, talk to other investors who have used them.

I’m listing it but one of  the FIRST things  I’m asking these days in my phone interview is to bring proof of past 12 months of payments to the landlord at the showing. 

Call your municipality's office.You should interview some professional home inspectors to get the list of what they cover. 

Interview a couple of agents or talk to other investors to get recommendations. 

@Kevin Stringari I have listened to interviews with one of the owners of those security deposit insurance companies and most of the time they will not pay out a claim unless you have a monetary judgement.

Bigger Pockets has so many interview videos with successful wholesalers, and here are some of my favorite YouTube channels to watch on that subject: The Dominique Effect, Brent Daniels, Max Maxwell, Kris Krohn, Phil Pustejovski, Clever Investor, Wholesaling, Inc., Propelio TV, Flipping Mastery TV, and real estate attorney William Bronchick.

I hope that makes sense but I would suggest interviewing some more lenders, specifically HML to find a more flexible loan.  

Some advice from our experience: look into a property manager with a great reputation and interview them like its a job interview (use BP advice to make sure you know what questions to ask).