To understand this benefit completely, you need to understand two financial terms- Capital Gains & Indexation. Capital gains are the revenue you generate by selling the property. Indexation is the method of adjusting the actual price of the property considering the effects of inflation on the property.
Rental properties are an asset for you. They draw a recurring monthly or annual income to you and therefore make you eligible for paying taxes on it. For example, if you have rented out a studio apartment or a home for rent, they bring you money. The government allows you to claim an exemption in taxation for various expenses. Repairing, maintenance taxes, property taxes, and insurance are some expenses. A standard claim is 30% of the new rental income to account for other expenses.