I am 6'8" and 255lbs so my figure is a bit between Kevin Durant (not as skinny) and Lebron (in shape but not as muscly). For smaller bikes such as what you would find in Wal-mart, I frequently see bike weight limits of 200lbs or so despite me still being able to still ride the bikes without any noticeable issues other than my knees hitting the handlebars. I thought bigger wheels (27"+ or 650b) would help, but I still see this weight limit which is absurdly low IMO as I'm a pretty skinny guy.. I saw another bike that had a suggested limit of 300lbs, but the recommended height limit was 5'7-5'10. Then I found another bike which claimed to support up to 6'3 and 220lbs, but the bike frame was smaller than all of the others at 17" where the others were set at 18".
Because I'm looking for bikes under $500 so that I can ride around my neighborhood, I'm going to have to compromise in some size aspect but am not quite sure which size aspect matters the least: bike frame size, recommended weight limit, or wheel size. I saw other questions about tall riders but nothing specifically addressing this aspect.