Milwaukee has a great stock of 2 family properties; which I would favor over 4 family as they tend to be in lower grade areas.

Depending on how much they like you, might mean a lower down payment. 

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

Depending on the quality of the finish, the building size (the larger the size the lower the $/sqft), your level of experience, etc.

It used to be a cash-flow goldmine for lower-end SFR’s.

The lease payment replaces the electric bill, often with a lower amount, so from a cashflow angle it usually improves the customers position.

Negotiate a lower price if inspections warrant that, do a walk through the day of signing, and if everything is still okay--no squatters etc-- go sign the papers, pay the money, get the keys, change the locks and move in...I would guess I might have missed a step or two...

It will be lower in years 1 and 2 during the value add and increase from there. 

Often times this can be a win-win, even if your offer is lower than others.

A good strategy is to use the LOC to make an all cash purchase, that way you increase your bargaining position, then once the property is yours, get a lower interest 30 fixed loan on it, & repay most of your LOC.