What to look for when purchasing violins?

When purchasing a violin you could always ask what the material/wood that makes up the belly is. Depending on the tone that you would like to achieve, look at the curvature of the belly, compare it to some around in the shop/you own existing violin.

The bridge, sound-post and bass bar are all a bit more difficult to judge, as it is something that violinmakers take very careful consideration into when placing and making these components. Getting your violin checked out after having it for a couple decades is recommended as the bridge can start to move and go on a slight angle. Same goes for checking the sound-post and bass bar, you can take it to a professional violinmaker or violin handler for them to see if the interior is still in good condition (especially if you’re looking into restoring a violin).

You are actually able to purchase varnishes to apply to your violin. A personal recommendation from me is to seek help from a store that has a violinist/violin repairer/violinmaker, when buying the varnish for the first time, so they can show you how to apply it properly. Of the 2 different types of varnishes out there I would recommend an oil-based varnish for its long-term effects on the violins tone, a worthwhile investment.