And that is a big part of why AVs will be cheaper. Paying 1/10 of $500 a month is better than paying $500.
The cost will also depend on how big a vehicle you need. For many people going to work, they only need room for one person and a little space for cargo. Paying for 1/4 of a vehicle is cheaper than paying for a whole vehicle.
So even the variable cost of your transportation will go down.