To sell, or not to sell?

[Marc Silva]

Looking for some advice.  We recently moved into a new primary residence leaving our freestanding condo vacant.  The condo is worth roughly $360k.  Our 1st mortgage is for $144k @ 4%, and we have a 2nd through a private party for another $150k @ 8% that we use for our flipping business (3 flips under our belts.)  We can get about $1,800 per month in rent for it.  Without the private party 2nd we would have a nice cash flow of about $700/month, but we need that money to continue our flipping business.  Should we just sell the condo so we can get rid of the $12,000/year we owe in interest on the 2nd?  Or should we keep it for the future cash flow and continue paying the 8% interest only payments on the second?