depending on her budget and the timing of her visit will significantly affect her options. Boulder being a college town has a huge fluctuation in the available housing. If she comes in May or June there will be a lot of options, Aug or Sept things will be a lot tighter.
If she has transportation she then has the option to get something outside of Boulder county; one of if not the priciest rental markets in the state [which is saying something as Colorado recently placed three cities in the top 10 nationally for cost of rentals].
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