We went to see Juliette's house and found it to be the biggest waste of time and money across a three week trip. Admission to the museum costs €6 and my advice is save your money there is nothing of interst inside. Alternatively if you do wish to go inside, get a 2 day Verona card which gets you access to this and many other sites for only €15, thus it is at least cost effective.
All in all go there take a picture of the balcony from the outside and move on quickly to see the other sites that Verona has to offer.
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