I have tried different settings for the multiply by quantity etc. settings, but the result is the same.
This looks like a bug because when I filter out the whole day option so that only weekend reservation is available, then it will correctly show the weekend price and 3 days. If other price options are visible, it will show totally wrong price, and when I turn on an off different price alternatives it will change the booking in an unpredictable manner.
For example when I had two following weekends booked with only weekend price visible, and then turn on other price options, then it selected all weekdays daytime, thursday evening, the first weekend, and friday of the second weekend but not saturday and sunday. There is also lots of other strange behavior, and when I try deselecting days it will just show fix limit 3 error message.
Regardsless of any possible bad setup I have done, the booking calendar should not behave like this.
I can give you login to the site I am working on by pm or email so you can test this yourself. I can also help debug the problem if needed.