you loose 10% of the purchase price (if you gave them less for your deposit you will still need to pay the full 10%), and could possibly be liable for any difference in price if resold for a lower price to another party - but this depends on your contract. Often with long settlements you are unable to do 'subject to finance' because alot of financial institutions will not offer finance for to far in the future. You just have to wear the risk.

Find a good mortgage broker, you will be surprised at some of the deals they may be able to pull out that you didn't know about.