"Deposit money should always be paid to a law firm or other trustee, never to the builder, unless security has been posted with Tarion for the funds.
Purchasers whose deposits exceed $20,000 should always insist on getting a copy of the builder's excess deposit insurance to ensure that all funds above the Tarion cap are protected.
Ensure that the builder and project are registered with Tarion."
Your deposits are held In Trust by the builder's lawyer. You get a "Evidence of Compliance" letter with each deposit.
If the builder goes under you get the deposit back with small interest. It happened to me before and had no issues. However it may be a while before developer officially goes belly up and in the meantime you cannot use the funds elsewhere (i.e. 1 Bloor).