It takes about 2.5 hours and makes about 2000 requests to get through everything. One day of data is about 135MB, so the cost is basically zero.
First of all - I really love your program and think it is a thing of mathematical and programming beauty. Sure the interface is 1996 era Craig's list, but who cares as speed and data accuracy are the most important things.
Disclaimer - I personally used your site to search for a room and resort request that was sold out as I was checking every day or so whenever I remembered (but was unsuccessful) and within a few days of entering my request into your site I received an email on my iPhone that the room was available. I immediately booked the room and was SUPER HAPPY with the results. If I did not use your site, I may never have been able to book this room.
Let me make some guesses in regards of DVC server requests (feel free to correct these if you have better data):
If there are 400,000 DVC members and on any random 365 day of the year 1% of the members (4,000 members) make two online requests, that would be 8,000 requests for a typical DVC day. I would bet that half of all members still call the 800 number and do not use online booking, so my numbers could be high. Also, a typical online request will take something like 15 seconds, so I will estimate 30 seconds per member x 4,000 members per day = 2,000 minutes or 33 hours of computer power.
If you are making 2,000 requests per cycle and use 2.5 hours of computing time per every data refresh and you refresh 4x per 24 hours, then your grand total daily use is: 8,000 requests and 10 hours of server time
So, I estimate that you are currently making 50% of all DVC online room requests and using about 1/3 of their computer power.
What you are doing is similar to the high speed high frequency day traders and institutional investors where they are responsible for most of the movement on wall street, not the mom and pop investors.
I do NOT have any problems with you doing this, but Disney may differ and may try to halt this as if 2 more programmers developed similar bot programs to yours, then the majority of DVC computer power would be consumed by only 3 people or IP addresses.
Keep up the good work !!!