Mortgage Options for New Condo

What are my mortgage options for a new condo development? I know most of the building is finished but I know they don't have C of O, and am not sure if they have applied for other things. Most banks will require a certain percentage% to be in contract or sold, so I feel like I don't really have any options other than to wait for that % and write in a contingency plan with my lawyer if that % isn't met withing a certain timeframe. Any suggestions? I was thinking that I would go into contract and hope others will get into contract soon enough so that the % will be met...