Even though we are in the digital age, it still doesn't surpass good old hard copies of everything. I have had many different options to do my bookings completely digital. I have even though about incorporating into this very site a booking management system. All you would have to do then is answer questions to customers. It would allow you to not have to worry about booking overlays or anything. The problem with this is your relying on something that could fail. Or you might not have internet access one day. What I do instead is print out a calendar for the entire year. I then markup the calendars with arrows representing different bookings. I also mark last names on the calendar so I can look up their contract which I have set in alphabetical order for easy reference. Once the customer makes their final payment I highlight their booking on the calendar. Once I give them back their deposit I use another color. This way I can easily see which ones need to pay and who I need to pay back their deposits. Of course there are many different ways to keep track of cabin rentals but this is one of the easiest ways that I have found. And best of all you don't have to worry about your computer breaking down.