If keeping the property, she is getting a meager 2.4% return. With 2% of inflation, her real return is 0.4% annually. Based on this, I would agree with rapidestate. Sell the property and keep the profit without much tax consequense. I would be very cautious of buying another property right now, KN678 worries about the real estate market which is not without reason. But that does not mean that there are no good opportunities, I would buy another property if I can get a decent return, not 0.4%!
For now, I would put the profit in a short term investment and wait for the oppotunity either in stock market or real estate market. We all can see that both stock market and real estate market are hot, or you can say very hot.
If I were KN678, I would take the profit and invest in the stock market when the opportunity comes. I would invest in an index fund like 'VTI' which has a total return of 21% in 2017 with one of lowest risk profiles in stock market.
Here is the post I have written about a week ago when answering a question about investing in stock market in this volatile market.