Based on the mechanic of GTA Online. A mechanic will deliver your requested car to your position. You can only save 12 vehicles.

How to install:
Extract mechanic.cs, mechanic.ini and cleo_text folder in your Cleo folder

How to use:
You must not be in an interior.
Type "mechanic" while you are on foot, in a vehicle.
Your vehicles will be saved in an ini file. Mechanic.ini contains:
-Vehicle model
-Bullet-proof, fire-proof, explosion-proof, damage-proof, melee-proof
-Bass Boost (1=True, 0=False)
-Hydraulics (1=True, 0=False)
-Tuning parts (model of components, see veh_mods.ide, -1=not installed)
-Colors (primary, secondary, tertiary, quaternary)
-Variation models (-1=No variation. For rest of numbers, check Car variations section in Sanny Builder help (F12))
-Paintjob (-1=no paintjob)
To save a vehicle, you must be in a car or on a bike (planes, helis, boats and trains are not supported, to make it realistic), type "mechanic" and select "Save car" option. Select any slot and your car will be saved.
When you request a car, a mechanic will drive to your position. You can see a marker in the map to help you where is the car. Mechanic will exit the car when you are close to it. You can't request/save cars until your mechanic delivers your car (or the actor is killed or the car is destroyed)

Known bugs:
-If you are using car mods, be careful, it could crash the game, it depends if you car mod supports tuning.
-While saving a new vehicle, proof values don't save correctly in mechanic.ini.
-Exiting secondary menus don't work correctly.
-Mechanic will activate nitro, but when you enter in the car, nitro will be restored.

Author: Starblind94