I currently only have 1 duplex, however I want to set this up right so it will work for any size portfolio.Currently I haveHome folder>multi family/single family/legal documentsInside the multi family I have Name of property-> general property maintenance/first floor/second floor Inside of first floor (the one currently rented)I have, pictures (before and will have after) / lease documents / a spreadsheet with each month, what day rent was paid, if it was late, if late was fee paid?

Both are super nice people easy to talk too I’m just not sure if they have minimum size  def worth a call!  

Make sure the lender gives you what is called "Non-Dutch Interest" on the rehab portion, that means you do not pay interest on the rehab funds until you use them.

So they can do a 1031 only on their portion. 

@Jake HughesCost segs can be an amazing tax deferral mechanism but they are not a one size fits all solution.  

Most likely insurance is going to want the whole house not a shared portion of it.

Out of curisosity, are you considering utility reimbursement portion as "Owner making money?" 

It is 45'x20 total lot size and cannot be built on for setbacks, minimum house size, and more.

before you go down the rabbit hole to far as @Bruce Lynn mentioned see if the jurisdiction were the lots are located will even allow a surface operation within their zoning code or that lot size.. thats the first thing I would do.Being an old land man I have dealt with a ton of mineral and water rights.. there is a lot to those buggers..

I think the play would be buying a property that needs some rehab and you can split off a new lot due to new lot sizes and setbacks.