There are many things to consider before you buy a viola. The instrument’s tone and volume, for example, are two of the most important factors. Other considerations include how much you’re willing to pay, which size to buy and whether the instrument will increase in value over time. The appearance of a viola is probably the least important consideration, because an unattractive instrument isn't necessarily poorly constructed.
The sound the instrument produces is probably the most important factor when trying to buy a viola. It’s important to check that the tone of each of the strings is consistent before you buy a viola. If the tone changes noticeably between strings, then it probably is a poor-quality instrument. The viola is a relatively quiet instrument compared to others, so a high-quality viola will also be loud.
Your budget will have a large effect on the quality of viola available. Italian violas, for example, are widely considered to be the best, because they are usually handmade. This means the instruments come at a premium, however, so a tight budget may restrict you to factory-produced violas. Older violas usually have a better sound, because the wood becomes harder with age, but these instruments cost more than new violas.
The appearance of an instrument is not the most important factor when you’re trying to buy a viola. It’s natural, however, for people to choose attractive instruments, even if the tone isn’t as good. In general, it’s important to try a variety of violas — even ones that may not appear as attractive — because each will have a distinctive tone.
There is no standardization in viola sizing, so it’s essential to choose one that is comfortable for you to play. The longer a viola is, the better the sound, but the more difficult it is to play. The most common viola size is 16.5 inches (around 42 cm), so this is probably a good place to start. It’s also important to choose a string size that suits the size of your hands, because a large viola doesn’t necessarily mean long strings.
Other factors to consider when trying to buy a viola include whether the instrument is a good investment and where to buy from. Higher-quality instruments may increase in value over time, especially if they are handmade. Specialist viola shops are much more likely to provide a high-quality viola that’s set up correctly.