I'm not that fat, really. 221 at the moment with a goal of 175. I just call myself that for encouragement.

Yeah, the guy selling the bike probably measured the seat tube height from center of BB to top of seat tube. A roughly 58.5 cm top tube would put it in the 60-61 cm frame size I guess. But that does give me a better idea. I guess standover height would not be that significantly different.