If you need to do fixes on your own Husqvarna SM 50 S then it will always be recommended to own a Workshop Manual for reference in case you need to know the best way to take out a certain component like the Door and match it again efficiently.
Husqvarna SM 50 S Workshop Manuals offers clear certain diagnostic details for the car so if something is broken it can help you figure out what the problem is and how to correct it. You can then evaluate if you can do this on your own or that the job is just too big you can make a booking for your SM 50 S in with a local mechanic.
Husqvarna SM 50 S manual