Dave Ramsey has a good saying about how Thanksgiving Dinner is different when you owe money to the other person at the table.

I have been to the 3-day and it is a well run event, by professional persons. 

I personally like radiators, especially steam because the heating system is simple!

Personally, I would keep the property but I don't know your situation and if you could better use the money elsewhere.

Personally, if the property is in a bad area, this will give you headaches no matter what.

Personally we recently sold one of our properties with the sole purpose of paying off a loan of ours.

One of them I have used personally. 

Easy to use yourself too HELOC works (there may be some places that do a HELOCs on rental properties)I personally have used a 401k Loan on a few occasions - You're essentially borrowing money from your 401k and paying yourself back (interest goes back into your 401k as opposed to a bank) and if you don't pay your 401k back the loan would simply become a withdraw (maybe some tax penalties, but you could probably finagle a workaround).

I personally walked and researched every property prior to investing to understand what I was buying, what could be done to add value and what I should expect in cash flow and appreciation.Learning what makes a good investment for you is absolutely necessary. 

As a beginner, I would personally get my feet wet with something a little less risky without a balloon payment like that.