How to buy broken iPhones to fix? *UNITED STATES*

*I LIVE IN THE UNITED STATES*

Hi, I have a repair business and I want to buy broken iPhones to fix. I tried looking on ebay, but all the iPhones are either iCloud lock (which is impossible to bypass despite what some liars on youtube say), or they cost so much that I will not make any money out of fixing and reselling it. Can anyone please tell me where to buy broken iPhones to fix that aren’t iCloud locked or overpriced?