Tap a street name in the city to open the corresponding property panel. This panel gives you current stats of the property, which can be useful to complete missions dealing with properties.
You can also access the property panel by tapping the property button next to the building menu button. Tapping it will direct you to the nearest property's property panel.
The various stats visible in the property panel are: built (how many tiles are free or not), wealth (counting the wealth value of the property itself PLUS the wealth of any building placed in it), population (counting the sum of population of all residential buildings placed in it), rent per hour (counting the sum of the rent per hour offered by all residential buildings placed in it), max rent (which states what the max rent is, and how much of this max has been accumulated already), and finally full in (time estimate of when the property’s rent vault will be full and will not accumulate money anymore - this is key to manage your sessions and maximize the money you can collect!).
You can view more details for these individual sections by tapping on the blue arrow in the top right corner of the property panel. Tapping on each of the above mentioned stats will show you how each stat's value is calculated.
You can hide the extra details by tapping on the blue arrow in the top right corner of the property panel a second time.