The Penthouse is a luxury apartment that very few will be able to afford it in GTA Online. But you can still get yours without paying a single dollar and get it before even the update comes out.
Steps to get the Penthouse for free
To get the main Penthouse for free in The Diamond Casino & Resort you just have to link your Rockstar Social Club account with your Twitch Prime account. You will have immediately unlocked this luxurious home. It is important that you do it before July 28 because otherwise you will not be able to get this house.
Make a Lot of Money in DC&R - GTA Online Tricks
This process is very easy. You just have to click on this link and follow the instructions to get the reward. Don't worry, even if you don't have a Prime account on Twitch, you can have access to a free one-month trial.