If you’re willing to settle for older bikes from the 1980s you can get good bikes that run great as-is for about the price you’d be willing to pay. Honda Nighthawk 650/700 and Yamaha Maxim are real gems you should be searching for because they can be had DIRT cheap, are beginner friendly, and are shaft driven which means low maintenance. I’ve seen them sell for anywhere between $1k-$2k for models in fantastic shape for the age. The Honda Magna 500/V30 is also a good choice, bullet proof reliability though parts can be hard to find in the unlikely event that anything were to go wrong with it. Suzuki Katana 600s can also be had for your price range and are good bikes as well.