Yes, you can park during a current rental.
With SIXT share you need the car key, which you will find in the glove compartment. With it, you can lock the doors and move away from the car while the rental is in progress. The cost of the rental continues while the car is parked. At the end of the rental, please return the car key to the glove box and lock the car via the app.
With MILES, the parking mode is initiated via the hvv switch app. A car key is only available on the vans. Please note that parking mode is charged per minute. Instructions on how to do this can be found here.
With WeShare you can of course also make a "stopover". After you have parked the car, you activate the parking mode in the app by tapping on "Activate parking mode". Switching to parking mode also locks the car. You want to drive on again? End the parking mode by tapping on "End parking mode", which unlocks the doors and off you go. Without a car key - there is no such thing.
Note: If you forget to activate the parking mode, WeShare will automatically lock the car (engine lock). When you return to the car, briefly activate the parking mode and then exit it again. Afterwards, you can simply continue driving.
Good to know: The ID models do not have a physical handbrake. Simply activate parking by pressing "P" on the right side of the gearshift and you're done!