If you need to execute fixes for your Diamo Retro 150 then it is usually a great idea to have a Workshop Manual to use as personal reference if perhaps you want to know the way to remove a specific component for example Wheel Bearing and match it again adequately.
Diamo Retro 150 Workshop Manuals are able to offer exact diagnostic wisdom for your vehicle so if something is not working it helps you identify what the situation is and the best way to make it better. You can then evaluate if you can do this by yourself or in the event the job is too big you can actually make a reservation for your Retro 150 in to a decent mechanic.
Diamo Retro 150 manual