Where are the properties and heists in GTA V online?
Figured it out. Part of the problem was that the server situation on day one was preventing texts and calls from Simeon from triggering.
As you level he sends one telling you about purchasing a garage for your car. This happens at around levels 5-6. You can find all the properties by going to the in-game website: dynasty8realestate.com. The properties will also show up on the map if you drive close to them. They have a symbol that looks like a house; it's also very similar to the convince store icon.
By level 10 it looks like most of the available content has been opened up.
Heist are currently not available, and will arrive in a later update.
The levels bring forward things like property and more unlocks for your character and vehicles. The heists will come at a later update. Which will be in late may 2014.
As CaulynDarr Mentioned, you can go to the website in-game at dynasty8realestate.com but here is a list of all of properties online: