If you need to conduct maintenance tasks on your own TGB 303R 150 then it is always a good idea to own a Workshop Manual to keep just for a reference just in case you want to know tips on how to take out a particular component much like the Drive Shaft and fit it again accurately.
TGB 303R 150 Workshop Manuals will give detailed diagnostic details for the car so if something is not working it can help you discover what the situation is and tips on how to resolve it. You can then decide if this can be achieved on your own or in the event the job is too big you can still book your 303R 150 into a local friendly mechanic.
TGB 303R 150 manual