Keep in mind that some, such as Internal Rate of Return (IRR), require advanced computer calculation.https://www.biggerpockets.com/blogs/8814/73755-18-essential-metrics-to-a-complete-real-estate-investment-analysisAs far as finding multifamily properties, you'd find them the same way you find a SFR, and there are many, many ways to source them:By building relationships and letting everyone know you're looking for houses and apartments:https://www.biggerpockets.com/blogs/8814/72664-35-relationships-to-help-you-find-more-houses-to-flip-or-wholesaleLooking for them on the internet:https://www.biggerpockets.com/blogs/8814/72016-55-resources-to-find-real-estate-deals-onlineand, of course, locating them offline:https://www.biggerpockets.com/blogs/8814/71506-27-ways-to-find-off-market-and-wholesale-real-estate-deals-offlineBest of luck!

But generally I think you're looking at lower returns in the mid-term.

I would need more information on your goals, expected return, budget, Etc. before suggesting areas.

Biggest concern with any of the spreadsheets you download off the internet: nobody shows you monthly returns.

If you are looking for a long-term option, it would probably do the best for you in terms of total returns.

If they are going to exchange it, then I would generally assume they are more willing to do so for something in return.

Just know that your returns might be smaller and it could take a lot longer to see benefits.

In return I would offer my time doing somewhat menial tasks that can be easily delegated or something similar.Thanks,Xavier

One way I look at it is this - spend $15k to make $2640/year, which is a ~17% return. 

Our company specializes in offering completely passive yet double-digit return investment properties here in Cleveland, Ohio.