I think you can have any number you like ( as long as its not already taken ).It'd be more fun if they don't have to run concurrently i.e 12345678 , i'm keeping a record of all the work i've done so it will still be traceable . The number punches are over 100 years old.
you should charge extra for custom numbers like 666 or letters
you should charge extra for custom numbers like 666 or letters