Shaving Cabinets, sizes?

We're having shaving cabinets in bathroom & ensuite to grab a bit more storage & the vanity in the main bathroom is only 1000mm long. But from what I can find shaving cabinets only come standard in 900mm or 1200mm. My question is this would it look wierd to have the shaving cabinet either of this sizes, so slightly longer or shorter than vanity?? Or should I fork out for a custom to have it the same? I really don't want to shorten the bench to 900mm as it's short enough. Could anyone give me an idea of $$ for custom made ones??

Price depends on how many doors you want and if you want polyurethane panels on each side.

For a standard custom built 2 door shaving cabinet you are looking at around $500-$600 pick up.

If you aren't having one custom made to match the size of your vanity cupboard go with a smaller wall cabinet than vanity not bigger. Balance it evenly above the vanity cabinet.