You have to sell it at higher price, otherwise it's a negative cash flow property.
Unlike you said "every property has positive cashflow as long as you don't sell at a loss". Be careful here, you have to calculate IRR very year. As long as you don't sell, it's always negative cashflow for your low rent property. The truth about IRR is the efficiency of return. If you don't sell, and no positive cashflow collected each year, there's even no return. It's only qualified to be positive after you sell it at higher price.
