It is VERY late in the game to even be considering this but the opportunity has JUST come up to do a haunt this year at a flea market. It is just meant to be an extra attraction for customers and vendors and will only be be open during the daylight hours on weekends beginning 2nd weekend of October. The owner will provide the space free of charge (some materials and advertising) and we will provide sets, props and actors (i.e., family and friends). Charge will be low - probably $3 - $5 and possibly free for vendors. We are not expecting anything more than an exhausting experience money wise and are ok with that. We have been doing it at home for years with plans to go pro someday and have quite a stockpile of set materials (20x30 storage unit worth).

My post here now is to get opinions on the location.

There are a few possible locations. One location is inside near a food court with sprinkler system. It has has outdoor access with two external doors but is really small. Probably about the size of a 2-3 car garage. Lighting completely controllable.
Other locations are outside and much larger (at least double the size) - completely or partially sheltered (roofs and overhangs) depending on location chosen but for the most part, completely open and very bright.

Ideally, I would like the extra space but have never considered a daytime, outdoor haunt. There will be A LOT of kids but I don't want it to be completely lame. Is there a way to do an outdoor haunt during the daytime successfully? Any ideas?
With such a small indoor space and being already sprinklered, will it be a nightmare in regards to Fire Marshall? The owner seems to think not (they were recently inspected) but I'm not going to rely completely on that.

Personally, I would like to try outside (more space, less concern about Fire Marshall I think) to see if it can be done but need someone to help me trigger should creative juices on doing that.

Again, I know it is really late in the game but I think it can be done. Any and all ideas and thoughts greatly appreciated. Thanks!