Milwaukee REIA and of course Brew City REI (disclosure that our company is an administrator of this group) are very active groups. 

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!

This, of course, generates a tax bill.If you are self-employed with no employees then you can set up a self-directed solo-401k with checkbook control. 

Omar, I prefer a one size fit all spreadsheet. 

I believe its currently around 3%; of course the tax benefits of this investment is nice as well. 

Just looking at ways to get as many units as possible (good deals of course).

Of course, all input is appreciated.

The balloon is due in August, the taxes are delinquent and the buyer is not paying them and my bank is threatening to call the loan, and of course they do not know I no longer own the property. 

Of course, they will need to be able to carry the note and have cash reserves for the other investment, so it is a bit of a long shot...

Might not be the BEST time to buy but if you come across a deal that fits your numbers I would not hesitate.