I understood that and I said that I knew that I needed to set the cost per day to use the Valuation days feature but, try to understand that I need to set the price for each resource per night, that is mandatory to my client!
When someone books a resource for several days the final cost is calculated by the cost per night (base price + 10% VAT). If someone books a resource only for one day the cost should be calculated also by the cost per night (base price + 10% VAT) + 10% extra fee (because is booking only one day).
So if I set the price per day like you are saying, the final cost will be calculated by the cost per day (base price + 10% VAT + 10% extra fee) and then in the Valuation days I would need to set the price for a 2nd day without that 10% extra fee, in case someone books more than one day.
It doesn't make sense because it's like working backwards and because that extra fee is an exception, and not the other way around...
Is there any way to make the valuation days work with the cost per night? Or is it something that you would change or a next update?