I'm looking for 3 or 4 star hotel with breakfast included and free cancellation
Retail price for Hotels in HK can be very pricey, well above 70 euros a night. Your best bet is to use Priceline. I once got a 5 star hotel for 120 usd. Otherwise, your best bet is to use a site like agoda.com and book a boutique hotel, those most likely will not have breakfast, but you're in HK!! There's food everywhere!
Maybe check the Dorsett Mongkok hotel, it's a 4-star hotel and I stayed there last time for around 60 euros per night (without breakfast) by booking in advance.
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