Re reporting of foreign property "--where the total cost amount --- any time in 2023 was more than $100K ." Does 'cost amount' mean cost when bought? Or current market $?

In Ontario houses are assigned a valuation by MPAC  for tax purposes every few yrs. In State we own condo tax is based on purchase price. We have no 'market value' until we sell. How do I interpret 'total cost amount' in this case?