Hello @Griselda76
I went onto your listing and can see that you have added an extra person fee that kicks in as soon as you put in 2 people for your search with increments per person until your total guest count! It's quite significant so this explains why there is such a big difference in the price per night.
You could decide to have a base price for let's say 4 or 6 people staying and then add an extra person fee after that. This will avoid having 1 person reserving the house to avoid the extra person fees.
I'm not sure how you can fit in 12 guests with the number of beds that are showing up on your listing though?
Check out the list of amenities again as there doesn't seem to be many that have been ticked for such a large place.
All the best
Joëlle