After considering the same issues, I bought one of these:
http://www.amazon.com/dp/B000LEI82W/...0&linkCode=asn
I have not used it alot yet but it is quite cheap compared to some strollers. It has caster wheels on the front making it easy to turn in tight spaces. I has a capacity of about 100 pounds if I recall. Because it is a double, designed for to car seats, the bottom tray is long and easily holds a large tripod without any need to strap it in. The thing folds up easily and is fairly compact. The "framework" design is suitable for easy mods and lashing down a variety of cases. I can put two pelican cases on the top for camera and film holders and still put a large tripod and miscellaneous loose stuff in the bottom.
The cons are that it does not have large inflatable tires for "off-road" use. So it is best for cities and buildings.
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