@Chan K.as others have said here... let her go and "take this loss"  as a huge WIN !

One bad investment that leads to a financial loss or foreclosure will damage your ability to continue investing in real estate for many years to come. 

Yes, you have not only the 6% commission but usually some other items when you sell.  

Cap Ex 5% - I figure this is a minimum to put away for the big items you know are coming...eventually.Management 10% - While I plan to manage the place myself, I also want to be able to hold indefinitely and know that if I take my REI where I plan to I will eventually remove myself from property management.Assuming the same 25% down and financing with a  30 yr fixed @ 5%, I get ~$120 monthly cash flow (not even my minimum of $100 per unit).

Final item would be is to have a meeting with the city people and see if you can do anything to use the full 4 appts with four meters.

Then estimate the value of your other assets like your car/truck, boat, other big ticket items. 

My partner and I used to handle all website/tech items - but now so busy we "sub" a lot of the work out.

In the same way as talking back to a police office might be more likely to land you a ticket.My experience with DNS is that they always seem to find something, but that usually the things they find are items that are on my list of things to fix.

Consider getting a property manager if you are not interested in dealing with the items below and treat the tasks like one would a business.

Converting passive income/losses to non-passive without an arms' length transaction in between would not be acceptable to the IRS.