If I move to a partnership, what happens to my accumulated passive losses? 

Taking the loss now is preferable to paying out monthly for the privilege of being a landlord.

If indeed a loss is taken on this which it sounds like is a fair possibility then if the agent was representing you the agents E and O will/could kick in and that's where you might get some financial relief.

Sell at a slight loss.

You will have to gather more accurate operating costs (vacancy loss, taxes, utilities, insurance, mgmt fees, maintenance, HOA) to best determine potential future performance.

It may be time to cut your losses and move on from this real estate. 

They have no ****ing idea.Your $500k salary likely has a 401k, health, vision, dental, etc.

I do this at least quarterly for some of my clients and they like being able to see the profit and loss reports. 

Quote from @Christian Pichardo: Quote from @Caleb Brown: Should you cut your losses and move on?

If I had to pay my cleaners on top of the loss income it would impact even more as my cleaning fees range from $100 to $400 depending on the property.