Hi Esther! I just wanted to revisit this thread to answer your question a little bit. So the original post described a case that was pressing on the bridge and strings of the violin, which is an indication that the case is a bad fit for the violin, and damaging the violin gradually by crushing down on the bridge. That is why I recommended buying a new case.
On the other hand, an old beat up case can be fine, but they are usually not well padded. So make sure the violin doesn’t move around within the case when it’s closed. A case should protect the violin from moisture, too. So if there are holes, or not a good seal when closed, I advise a new case. When thinking of a case that is in bad shape, it might have these problems, or it might not stay closed, that’s not good. If you’re case might fly open unexpectedly, time for a new one.
Cosmetic flaws do not matter. Integrity damages ARE a problem. The case should protect the violin based on your lifestyle, too. If you carry the case around a lot of people, like riding the metro or school bus, where it could get knocked around, I would definitely make sure you had a hardshell case that would protect the violin from impact if dropped or bumped around.
There is also the bow to consider. It may be hard to believe, but I have seen cases so old and beat up that one of the bow ‘hooks’ was broken, and the bow just dangled from the tip. Bad for the bow and potential to scratch the violin. Also if you have more than one bow, or plan to have more than one, be sure your case provides that feature.
You might also rather have some extra pockets than an older case provides, so you can store stuff we violinists tend to collect. These newer cases have provided very roomy options for us violinist/ packrats. 🙂