The entire exchange period is only 180 days so the max your money will be tied up is an additional 135 days.And there's another silver lining - depending on how the dates line up your 180 days may not end until 2019. 

For replacement costs on my average deal, HVAC is 3-5K, roof 5-6K, water heater $1K, and foundation can of course vary depending on severity and whether slab or pier and beam as examples.Third, decide if there will be any additions, conversions or demolitions whether adding a bath, converting a room to something else, or removal of walls to open up the space. 

The roof is leaking in additIon room.

Shray a few things to consider:With conventional lending, there are add-ons (points/rate) for non-owner occupied and additional units.  

If someone wants to put up some of the money and be an owner than either that person doe a loan to the company in addition to his ownership or He or she can get a preferred return from the membership of the company.

If it were me, I would be reluctant to assume much at all about their knowledge level and areas of expertise.Happy to help if you have additional questions or thoughts.

Additionally, when you get to the property management side, there are clauses that completely misalign the incentives between owner and manager. 

Additionally @Jeremy Hua, central Ohio is more than just Columbus.

.- The home insurance after the sale (the new owner is the "insured") should retain the name of the previous owner(payor of the bank note) on the insurance as "additional insured" so as to not set off any alarms with the bank.- Use a 3rd party loan servicing company to collect all mortgage and escrow payments and make all appropriate payments to the bank lender as well as seller finance lender.   

There are limits on them and if your policy only covers 4 rentals, but you plan on acquiring more, you'll need another umbrella policy for the additional units.