The job can be taken in 3 places around the map of SA
Los Santos:Near the Vinewood Cemetery
San Fierro:Next to the Cranberry Station,where Train Driver can be found
Las Venturas:Next to the Car Dealership of Las Venturas
How can I earn money as a Mechanic?
As a Mechanic,your main duty is to repair damaged vehicles.To repair a certain vehicle,press X to show your cursor,then left click on the damaged vehicle and press Fix Vehicle.Then,the vehicle owner will be notified with a question whether he wants his car repaired by you or not.If the owner accepts,then your character will start an animation,thus repairing the car.
But,repairing vehicles isn't the only way you can earn money as a Mechanic.You can also start a Towing Mission,by pressing N while being at a Towtruck vehicle.Then,you will be assigned a Mission where you have to Tow a vehicle back to the shop.As soon as you press N,a blip will appear on the map telling you to go there.When you arrive,align the towtruck in a way that you can tow the vehicle.The tow can be handled by pressing NUM8 and NUM2.When you have towed the vehicle,drive back to the shop and leave the vehicle on the marker and get paid.
General Information about the Mechanic job.
Levels:
Level 0: Tinkerer
Level 1: Student Mechanic
Level 2: Unlicensed Mechanic
Level 3: Certified Mechanic
Level 4: Auto Technician
Level 5: Auto Specialist
Level 6: Senior Auto Specialist
Level 7: Expert Mechanic
Level 8: Executive Mechanic
Level 9: Chief Executive
Level 10: Master Technician
Hourly Wage: Stats show that Mechanics can earn approximately 40 to 50k per hour,depending on how hard they work or how many vehicles they repair.
Tips and Tricks
Here are some Mechanic tips as to how you can earn the maximum money but also ameliorate your experience.
Advertise yourself as much as possible,without spamming,and tell them that you cost less that a PnS repair. (20% less)
When nobody is looking for a Mechanic,do Towing missions as much as possible to earn money.
If you don't want to do Towing missions in a certain city,roam around SA preferrably in places where fights are happening or places where many people are located.There you might find vehicles to repair and earn money.
Keep in mind that towing missions do not give job progress,meanining that you need to manage the time you spend doing them.
The best places to do the Mechanic job are: LV due to the turfs=many people=vehicles to repair and SF if you want a calm time towing vehicles.LS might be good in some cases,but I won't recommend doing the job there since the city is dedicated to other activities rather that Civilian jobs.