If you want to do repairs for your Polini XP 4T 110 then it is usually recommended to own a Workshop Manual to keep just for a reference in the event that you want to know how to take off a specific part for instance the Brake Discs and fit it again accordingly.
Polini XP 4T 110 Workshop Manuals provide you with certain diagnostic guides on your vehicle so if something is playing up it can help you find out what the issue is and ways to resolve it. You will be able to decide if this can be achieved by yourself or that the job is simply too big you can make a reservation for your XP 4T 110 right into a decent mechanic.
Polini XP 4T 110 manual