How much money?
IF the LBS has ANY integrity, they will allow you to use THAT money on something else they sell -- for example, tools, tires/tubes, cables/housing ...
Now, whether or not there is anything else they have that you want at a reasonable price is another issue ... now, or in the future.
OR, better, they will just give you your money back! Tell them you have unexpected expenses & won't be buying a new bike until _(whenever)_.
If they just refund the deposit, then thank them profusely & give serious consideration to patronizing them in the future IF they have something you truly want/need!
IN THE FUTURE, actually do some research before rushing out to a store to buy a bike/car/anything until you have a better idea of what you are looking at.