With a purchase the tax is usually calculated on the purchase price.
If you acquire the property for consideration through a purchase, the real estate transfer tax is 3.5 percent of the consideration. The basis of assessment is the purchase price together with assumed encumbrances, but at least the property value. The tax is usually self-assessed and remitted by the party representative. An estimate of the total incidental purchase costs is given by the incidental costs calculator.
Have the basis of assessment and the self-assessment coordinated before signing.