At her height, I would look for 26" on a nice HT bike - or maybe even the 27.5 HT. No need for the full sus with that kind of riding plans. I know some people will say you should go 29er -but I would say not at her height and at your budget. The weight of the bike will be crazy and she will have difficulty pedaling up hill - cheaper 29er bikes, even in the women's specific are about 30lbs. It's also a lot harder to maneuver the longer wheel base around tight corners and requires more strength to get over some obstacles. Find one that fits first, then analyze what you can afford. Specialized only makes 29ers now, so although I love their bikes, I would suggest looking elsewhere. (unless you want to really surprise her with the small Fate - carbon 29er HT that's light, fast and fun. But also way outside price range...) Giant has a 27.5 Women's HT that's about 1500 with decent components and such. I really haven't researched MTBs in that price range too much :)
I would stick with a real MTB, not a hybrid, so if she does start wanting to do more, she can. Hybrids aren't really fun for most trails and even some of the fire roads around here. Absolute must - disc brakes. Doesn't matter if they are mechanical or hydrolic, but the disc brakes provide the stopping power needed for gravel, trails and wet conditions. Anything Shimano or SRAM for components will hold up for years under those riding conditions. The budget buster will be the fork - better quality = more $, but a smoother and more fun ride.
Hope that gets you started with the hunt.
Vale!
Tracy T
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