They can really help increase your business. Your site will attract more visitors and begin to work for you. For example, the booking systems will not only increase your bookings but will free up more of your time (less time on the telephone - particularly beneficial at night).
One other benefit - recently a local guest-house owner said that of the £2,500 they had taken through online bookings in the previous month (using another system), they had to give £650 in charges for the online payments. With our systems the charge (to PayPal) would have been about £25 - and there are no other charges with our system.