Edit #1:

Payment Policy
All reservations require a minimum of 50% deposit with a maximum of 7 days after the date of booking request.

Payment Policy
All reservations require a minimum of 50% deposit within 7 days following the date of booking request.

Edit #2:

** If you cancel 8 weeks or more days before departure: Cancellation fee is 15% of the total deposit made.
** Less than 8 weeks or 2 weeks before departure: 50% of the total tour price or equal to the amount of deposit is non-refundable.
** Less than 2 weeks or 48 hours before departure: 90% of the total tour price is non-refundable.
** Less than 48 hours before departure: 100% of the total price is non-refundable.

** If you cancel 8 weeks or more days before departure: Cancellation fee is 15% of the total deposit made.
** Between 8 weeks and 2 weeks before departure: 50% of the total tour price or equal to the amount of deposit is non-refundable.
** Between 2 weeks and 48 hours before departure: 90% of the total tour price is non-refundable.
** Less than 48 hours before departure: 100% of the total price is non-refundable.

Suggestion:

The final payment being received upon arrival might not be a great idea if you have a tour lasting less than 3 days. It could mean that someone purchases the tour last minute, and either cancels the day-of, or doesn't pay the remaining balance of something (like a hotel) where you may have needed to put the money up for before receiving full payment.

You may want to add something where last minute bookings are paid in full (or the percentage mentioned in your cancellation policy needs to be met based on when someone books); so a person booking within 2 weeks, but more than 48 hours, of the tour requires a 90% down payment upon booking.