Things to consider when choosing the best guitar amp under $200:
1. Guitar Tone
There are many amps priced under 200 bucks that sound like exactly that - cheap. The amplifier's listed above are of great quality and speak for themselves with great praise for their overall sound. You can typically get a good understanding of how they sound just by listening to them even through a simple youtube review.
2. Speaker Size
The size of the guitar speaker will help determine what situation you would be able to play the particular amp. Smaller amps are more difficult to play over a full band if that is what you are going for so you definitely want to keep that in mind when choosing a great amp under 200 dollars.
3. Guitar Amp Power
Guitar amplifier power goes almost hand-in-hand with speaker size as typically the lower the wattage of the amp, the smaller the amp speak is. Now perhaps you're not looking a 'loud' amp at this price range, maybe you would want to compensate volume with more features and tonal quality - this is all up to the player.
4. Tube Guitar Amp vs Solid State
Solid State and Tube amps have different qualities which make alternating so much fun. Tube amps are overwhelmingly the preferred choice due to their 'warmth' tonal quality and great natural tube overdrive, though typically expensive. Solid state amps are much more durable, and you can get super clean guitar sounds while still playing loud.
5. Guitar Amp Effects
Many guitarists at home or on the go don't want to deal with the hassle of setting up their guitar pedals or pedalboard so having a great set of already built in guitar amp effects will help these low cost amps even more. Most amps will already include some sort of overdrive / distortion and reverb, but some also add additional effects such as a delay, phaser, chorus, etc.
6. Guitar Amplifier Features
Lastly, don't disregard additional features - that's what makes alot of these amps stand out. Some add built in tuners, line outputs to plug directly into your computer to immediately start recording, headphone jacks to play loud in your ear and not your family and neighbors.