Jeans and trousers are alterable these days. Custom jeans are becoming more and more popular. So buy them the way you buy a trouser.

If you find a well fitting pair, always buy two, one to wear with flats and the other to wear with heels.
Jeans work well on all women, regardless of age, size, etc., but not all styles work for all women. Wear a style that flatters your figure.
For your office, you may wear the slight boot-cut, trouser-looking jean. A dark wash pair, doubles up as a trouser. They look great with a pointy toe as it creates an illusion of long legs and makes you appear taller and slimmer.
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