Property tax is a wealth tax on you property. Whether the property is for own stay or for rental you have to pay property tax. The amount of tax is determine by the property Annual Value (AV) multiple by the prevailing tax rate.
Property Annual Value
Singapore Tax Authority – Inland Revenue Authority of Singapore (IRAS) determine the property annual value (AV) basing on rentals of similar properties. You can find the AV of your property by login into your personal mytax portal. In your tax portal go to Property -> View Property Portfolio then click on View Details