Calculate the "Add$-$On Total" for the first transaction. Rooms with $3$ or more guests are required to pay the add$-$on fee.

Use an IF function with a nested VLOOKUP to calculate the total based on the number of guests, number of nights and the room type.

Use the data in P$4$:Q$6$ to look up the cost based on the room type.

The add$-$on fee is per person per night.

If there is no add$-$on fee display a zero $(0)$ in the cell.

Copy and paste the function down the column to calculate the add$-$on total for the other transactions.