Legal Clinic for July 2015

Chris Tan returns to out monthly property legal clinic to answer the following query from our listener, Sean Lee:

After putting my property on the market for nearly a year, I finally got a buyer, after adjusting my price. She has duly paid the booking fee and the ten percent after signing the SPA. However, its been four months since the SPA was signed and unfortunately, she has yet to get financing. Her excuse is that she hasnt gotten favourable rates. I am tempted to cancel the purchase and put it back on the market (although the market isn't doing terribly well either). Am I allowed to do so in the first place and am I entitled to any penalty in the meantime?