To give you an example:
Purchase price :$200.000
Deposit paid to the builder :20% / $40.000
Remaining balance due to the builder : $160.000
You have to pay interest to the builder for this remaining balance. They normally take the 1 year Mortgage interest rate posted from Bank of Canada, which is 3.75% now.
$160.000x3.75%=$6.000/12=$500 monthly.
On top of that you have to pay the condo fees, let's say $200 monthly and also property taxes, calculated based on your purchase price and the property tax rate, let's say 200.000x0.08=$1600 a year - $133.33 monthly
The ocupancy fee will be $500+$200+$133.33=$833.33 monthly until final closing. depending on the building you also need to pay hydro separately.