Hi @Jennifer-Ife0
On Airbnb, enter the search term that you think most of your guests will use, a date range and enter 5 guests. Look at the first few listings and note their total cost. Do the same for 6, 7, etc. guests. You will now have a list of prices that rank well at each guest count.
If you want to, you can also click some of the 12-guest listings and (on their calendars), check by how much the total reduces when you change to 11 guests and so on (keep dates steady).
Keep in mind, all these prices include service fees and possibly taxes - your own rates will have to be lower in line with that.
As for choosing the date range, it may be good to choose dates that you have available and want to sell soon, but keep in mind that some well-ranked listings may already be booked.