By selling first, you can avoid paying two mortgages simultaneously for an unknown period of time. It also means you know exactly how much money you can spend on the new property. To know for sure, you have to investigate the state of the market, identifying whether it is a seller’s market or a buyer’s market. This, more than anything, can have a huge impact on your decision, because if your home is likely to sell quickly, you’ll need a back-up plan in place to help you cope in between properties.