Get a property in — from its tenancy contract, or by typing the address.
Your first property comes in during setup. After that, add each one from the Properties page.

If you share the property, click + Someone else owns part of it under I own it personally and set the shares. See Jointly owned property. With My company owns it, pick the company or add a new one. Tick Held on trust only if the title is in someone else's name. With I manage it for its owner, enter the owner's name. See Managing a property for its owner.
You can change the answer later. On the property's Finance tab, select the button beside Rent status, then Change who owns it. That opens the Who owns this property? window, which offers the same three answers as Me, One of my companies and For someone else.
The next window asks What kind of property is this?

Click Residential for a home let to tenants. The property is added as soon as you click it. Click Commercial for a shop, office or unit let to a business. It asks a few facts about the premises first, and you add the property with Create property.
The property is then in, vacant, with no tenancy yet.
You are then offered the tenancy contract. Add it — a PDF — and Alfred reads the tenant, the rent and the dates straight off it, so the property arrives filled in rather than blank.
It is optional: Done finishes with only the address, and you can add the contract later from the property's Documents tab.