They just announced at PAX that Lincoln customization and deeper car customization will come to Mafia 3 via free update after launch 
Beside that free updates will include weapons, vehicles, car races ect.
You can read about updates here
https://mafiagame.com/en/news/view/en-a-look-at-the-post-release-content-coming-to-mafia-3
PAX presentation
https://www.twitch.tv/pax2/v/87365037?t=03h11m07s
Beside that free updates will include weapons, vehicles, car races ect.New Bordeaux is a big place – it’s loaded with history and hidden alleys to explore. When we built the world for Mafia III, we wanted it to really feel alive and grow with you. We’re doing just that with free, recurring content that gets delivered to everyone who buys the game. If you love your time in New Bordeaux and don’t want to leave – we’re also working on unique story expansions coming to Mafia III.
First, let’s talk “Free recurring content.” For everyone that buys Mafia III – whether it’s through pre-orders, day one purchase or those who wait – we’re delivering free new features and content after the game launches. Here’s a quick rundown of what you can look forward to:
FREE! All New Character Outfits
One of the biggest requests we keep getting from you – our fans – is about the ability to change Lincoln’s outfit. This is coming! New outfits will allow you to select a look that suits your tastes and define your take on Lincoln.
New, FREE Weapons
30 days after the game launches, everyone gets the “Judge, Jury and Executioner” golden weapons pack.
MORE Vehicle Customization
Hey, gearheads: We’ll be expanding upon the vehicle upgrades that already exist in Mafia III by adding new customization options. You can cherry out your favorite ride with new wheels, personalized license plates, and paint jobs. And, yes, you will get even more options to boost the performance on your vehicles.
FREE RACES!
Take your tricked-out fleet into the city and enter a series of races. From there, you can earn money, new customization options for your car, and other awesome rewards. We’ll have more details on exactly how the races will work in the future.
…and more free stuff to come!
MORE STORIES FROM NEW BORDEAUX
Now, like you, we are all gamers here at 2K. We know what it feels like to finish a game and want more – more story, more locations, more action. So, now that we’re doing some final polishing up on Mafia III before the October 7 launch, we’re starting work on new story expansions. These are wholly separate experiences that reveal more about Lincoln Clay’s time in New Bordeaux. As these stories will reveal, the Italian Mafia isn’t the only threat Lincoln faces…
Here’s a quick tease of the three major paid expansions in the works…
“Faster, Baby!”
Fast cars, dramatic chases, and stunt driving take center stage as Lincoln joins forces with his former flame, Roxy Laveau, to take down a corrupt Sheriff terrorizing Civil Rights activists on the outskirts of New Bordeaux.
“Sign of the Times”
A string of ritualistic killings has New Bordeaux on the edge of terror. At Father James’ request, Lincoln agrees to hunt down the cult responsible, a quest that will take him from the dark heart of the old bayou to the drug-ridden counterculture of the inner city.
“Stones Unturned”
When a merciless rival resurfaces in New Bordeaux, Lincoln must join forces with CIA agent John Donovan to settle a blood feud that began in the war-torn jungles of Vietnam.
Along with new story and character additions to New Bordeaux you’ll find new activities to engage in to expand and diversify your criminal empire. And, yes, these paid expansions will also offer exclusive vehicles, weapons, outfits and races based upon their themes.
If you buy the Season Pass, either on its own or through the Deluxe or Collector’s Editions of Mafia III, you’ll get access to these three new story expansions and all the weapons, vehicles and gameplay that comes with ‘em. If you don’t feel like buying a Season Pass, that’s ok, too, because each one of these stories will be available for sale individually.
One head’s up, though: If you buy the story expansions separately, they will run you a total of $39.97. With the Season Pass, you get them all for $29.99. (Or, if you buy the Deluxe Edition of Mafia III for $79.99, it includes the full game and the Season Pass – which saves you a total of $19.97.)
Looking forward to seeing you in New Bordeaux on October 7!
You can read about updates here
https://mafiagame.com/en/news/view/en-a-look-at-the-post-release-content-coming-to-mafia-3
PAX presentation
https://www.twitch.tv/pax2/v/87365037?t=03h11m07s
