We own two outdoor Trails and one indoor haunt. The outdoor is completely different than the indoor. With indoor you have one facade (for each haunt) and several rooms. Outdoor we build "sites" which is practically little "hut" styled buildings. Each building may have two rooms inside and generally aren't that big (depending on the site). Now here is the kicker each site has a facade. So our indoor haunt has two facades with 20 rooms in each haunt. Our outdoor haunts have about 18-20 sites each with their own facade.
Also there is the build time. Indoor you are working within one area (typically). Outdoor your event is spread throughout a trail that is about a mile long. Sure four wheelers and such help, but it kind of sucks when you get to the furthest point on the trail and realize you forgot a tool or board that is all the way up front.
I will say this though. I have sooo much more fun working on our outdoor events than the indoor. I can't really explain why but I do enjoy it.
I have always been told by some big people in this industry that Outdoor events generally generate more traffic than indoor. I don't have a direct comparison as our haunts are all in different cities (ranging from Louisville KY, to Fort Lauderdale FL). But from looking at other haunts in our areas traffic (parking lot, lines, etc.) it appears that we are doing more numbers on our outdoor than any of the indoor haunts. Now I know that lines and traffic can be deceiving because who knows how their throughput is, but we pump groups through really quick ourselves.
As far as the rain IT SUCKS!! The 2009 season we had to close EVERY Friday we were open and one Saturday. That totals to 8 nights being closed. Rain is a big issue. We don't call our event off unless we absolutely have to. We have tons of mulch on standby in case it does rain. But as long as it is not raining hard around 7 p.m. and the trail isn't totally washed out we open. We mulch the trail the best that we can, and explain to customers before they get their ticket that the trail may be muddy.
Any other questions feel free to ask.