Need suggestion, I want to back out off the offer, can I ?

[Daniel Wang]

So I saw a duplex on the market and put it under contract for 312k, I thought it was a good investment.

Fast forward, now the appraisal came out and was priced at $280k, after I did more research I realized that I was too optimistic about the rent I can get for that property. Now even with the apprisal price, I won't be able to get a good C on C return as I expected. My mistake of course. 

So my question is can I back off the deal at this point without losing my deposit?