In today's era of boutique pedals, I would suggest you narrow your choices down to the type of effects you're interested in. There are literally hundreds of choices nowadays. Consider what type of music you play, and as Harry suggested, looking at your amp setup may help steer you in the right direction.
Are you interested in reverb or delay? Modulation, like chorus, phasers, flangers, vibrato, etc.? Maybe boost, distortion, or fuzz? Compression? Is there a particular tone you're after or favor, like a Marshall Plexi, JTM45, or old Fender Tweed? Are you after a more analog or digital tone? There are great pedals for everything nowadays, including many that combine several effects into one. If you'e not really sure, it might good to play around with a multi-effects pedal to figure out what you like.
Strymon make amazing pedals, but they're pricey, even used. Every Wampler pedal I've tried has been super solid. I have a Dual Plexi that I love. Earthquaker Devices make some fun and wacky but excellent pedals. Their Dispatch Master is a cool reverb/delay pedal for $185 new. Anything by Robert Keeley is amazing. TC Electronics also make great pedals in your price range. Old school brands, like MXR, Digitech, and Electro-Harmonix are still cranking out creative pedals, too.