I'm short also-5'5"-and have had to be aware of bike height.You will get the most bang for your buck by doing this.
Get a decent-but older 1996-2002 MTB full suspension bike off Ebay.One with at least 3' of front and rear suspension.Gety one with the smallest frame you can find(14-17"-standover with2" tires will be 27-29") -that is still a good quality bike-nice components.For example-the older carbon trek Y bikes can be bought-with XT-LX components for $400 or less.The same goes for other high end bikes that are 4 or more years old-they sell for maybe 25% of new cost.
Now it gets a little tricky.Take the shock off-Get someone to cut a rectangular piece of aluminum-or steel to support the rear of the bike-cut it and drill it so it is just long enough to allow the rear tire to clear any hard part.Your bike will now sit low at the rear(high at front) and the standover will be about 2' less9you will have dropped the rear by about 80mm,but standover will be 50mm less).
The front end is a little trickier-if it is low enough-just leave it the way it is-nose up.If you want another 1.5" of standover(roughly 80mm total less than originally)-you have to remove the spring-or plastic 'spring" and then lock the tubes in the down position.I would be tempted just to epoxy the tubes.If it is a nice fork then buy a cheapo rock shock judy and use it as a solid fork-save or sell the 'good fork".
All this sounds complicated,but it isn't.Give me the dinensions and I'll cut and drill an aluminum strut for you.
The upside is that you can have high end good components with "normal wheels-tires.The 650c tires are expensive and you have a very limited selection of very high pressure hard riding tires.24"-more selection,cheaper but still nothing like the 26" MTB tires.Also,you can get very skinny MTB tires and very wide MTB tires-the 650-just skinny-the 24' just fat.You will also end up with a high end frame-components that can be sold to a wide market-the market for 650c and 24' bikes is very limited.All the changes-except maybe the fork-are reversible for future .selling.Luck,Charlie PS This should drop it to 25-26" standover-less if you go for skinny tires.I You can usually tolerate about 2' more standover than my actual pant inseam-you just tilt the bike a bit.
PPS-A Mixte frame is pretty nice also.I like them-I'm male,but some guys won't ride them.Standover for them is maybe 24"-no mods. Same story for some 20" folders-they are kinda cool.Might have to mod the seatpost or HB.
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