Be certain you've fully evaluated your cash flow by doing a cash flow analysis.I leave it to you to confirm you've taken in consideration the following potential costs: CapEx, maintenance, property management, water, sewer, trash, vacancy, turnover, taxes, insurance, etc.

If you're in Northern MN, there is a very good chance that the cost to build a new duplex exceeds the resale value, which would be an awful idea to build a new one. 

Next up is a huge financial hit: closing costs.

You could easily be $100k in for water/gas/power/sewer if you’re talking 4+ lots. 

When a PM does charge a markup, he's usually getting a discount on the service to keep the cost stable.

They were seeking secondary homes for their family that could be rented to help offset costs and didn't require an immediate or transferrable permit.

That said, don’t underestimate the power of building relationships before you pitch a deal.

Let's use that as an example. 20% down is $43,000 plus lender loan origination fees, closing costs etc is going to push you over $50,000 cash out of pocket.

A manager will roughly cost $100-$150 a month to take over a unit (it could be more or less in your market) and manage the units.

Can she pay you that same amount to cover some of the costs?