Can I add/remove someone as a co-purchaser or co-owner of the property?

If you want to add or remove a buyer after you’ve already signed a purchase contract, you may be able to do so by executing an addendum or assignment of the contract. You should discuss any changes to the buyers and/or the type of ownership with your lender if you’ve already arranged for financing. Changing ownership once the purchase transaction has completed is a little more involved. In that case, you may not only have to consider the effect that change will have on your mortgage, but also the payment of additional legal and Land Title Office fees and potential property transfer taxes.