Another consideration i've not seen mentioned here is overhead clearance. Watch out going through 'drive through' things like fast food restaurants, overhead canopies and such. Bank drive-up windows often have overhead items you can impact. Sometimes pedestrian crossings can be too low for what you're driving. The ultimate in this regard i've heard of, was a new fire truck at Milwaukee International airport [Wisconsin]. The third day it was there, they had a lorry smash on the interstate. It was an aerial foam truck - capable of squirting foam over a 747 aircraft (all the way over). Needless to say, it was rather tall. They ripped out of the fire station (on airport grounds), opened the radio-controlled gates out into the public area, went through a parking lot + out onto the public streets. At the first two intersections, they snagged + tore down 3 sets of traffic lights - which controlled 6 lanes of traffic. Measurements showed that they would have cleared the 6 lane underpasses over those intersections by 4 inches (just enough). The traffic lights are now on posts along the streets - no overhead wires. Cheers.