Tell them you are interested and you would like to know how you might be able to structure a deal that works for them.

This structure is most common but could differ if your agreement is written differently. 

Perhaps if you really want to get involved with real estate you might want to consider looking into a REIT rather than physical properties so you can be hands off. 

In Dodd Frank, they anticipated that some might carry paper to get around Dodd Frank (not that you are doing this) and therefore they also "cast their net" over seller carry backs.Most importantly, please don't rely on what I say, except to inspire you to seek legal advice (which I am not qualified to give) from a qualified attorney in this area, and structure this so it doesn't get you into legal tangles or possibly worse, interaction with the CFPB.

But after reviewing some of our portfolio he spent an hour asking us how to structure an owner hold & the pros & cons of being a Landlord. 

Go hire one tomorrow to review your contract and set up your business structure for the purchase.

Then we have to exclude Physical Vacancy and Economic Vacancy to get to our Gross Operating Income, right? 

(economical vacancy, physical vacancy, jobs, population, etc)? 

With that in mind, one of my real estate investor friends is strongly pushing me to build a trailer and/or RV park instead of pursuing SFH’s since I have the ability to build all of the infrastructure myself.So I’m curious as to whether anyone has any advice on the best way to structure an investment like that.

If not, give details on why you expect to get the contractShould Haves Did you physically see the propertyDo you have partnersHow was the ARV determinedDo you have an appraisal or BPOIf it's a rental unit, does it have renters, how close do you live, will you be managing itWhat is your exit strategy?