Originally Posted by
Road Fan
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Regarding sizing, if you can raise the saddle to a good height to get adequate leg extension, lower the bars to about level with the saddle, and have a comfortable reach to the handlebars (this is hard to quantify), the bike could be a good fit.
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You can raise the saddle if it is a bit too low, but you can't lower it if its lowest position is too high. The OP says that she is 5'4" and that the bicycle has a 22.5" seat tube and 33.5" standover height. Given these measurements, I would say that even in the lowest possible position of the saddle, she will not be able to fully reach the pedals. A bicycle in this size is suitable for a person 5'6" and over.
Edited to add: Luckily, it is actually much easier to find a mixte with a smaller frame than with a larger frame, so I would just keep looking. I think a 19" frame would be good for your height, and these come up pretty frequently.