Undercoating is just horrible. I did it for a while way back. If you do it yourself and do wheel wells, etc... It's OK. When we used to do it at the Ford dealer, we sprayed drive shafts, exhausts, axles, oil/trans pans, calipers, rotors, - whatever. Nobody cared. It was such a mess. It got in your hair, on your skin, - everywhere. All the other cars in the shop at the time got overspray all over them. If someone complained, we just wiped their car down with Ardex solvent.
We loved it though. It payed 1.2 hours flat rate. 0.2 an hour to undercoat and then you spent like a half hour cleaning it up and picking it out of your hair. We were too stupid to wear a hat. Then one day, we came up with "the undercoating hat". Everyone wore this nasty ski hat to undercoat. Eventually, the hat was just undercoating - you couldn't see the actual hat any more. Then a rumor went around someone peed in the hat. So, nobody would wear the hat anymore. It was easy money. I used to take up 3 lifts and hit 3 new cars at once with undercoating. 3.6 hrs in 10 minutes. Then came the clean-up. Pretty soon all the safety latches on the lifts got gunked up with undercoating. Again, nobody cared. We used to take the spring mechanism off the lift lever so we could jamb it up with a brake clean can. That way, you didn't have to worry about the lift bleeding down on top of you since none of the safety locks worked. It was constantly trying to go up.
Most of the undercoating was done at night after the service manager left. Someone would get cases of beer or Mickey's Malt Liquor. There was an old guy there who always had a big bottle of Bushmills. Then we would start undercoating new cars. I remember spraying a bunch of undercoating in a guys beer can and wiping the lid so he would have no idea when he took a sip. After he drank it, he poured like 5 quarts of oil in my tool box. At least it was fresh oil. So, then I got a chain and stole his tool cart. I chained it with a lock to the back of his truck. When he went to pull out to go home, he was dragging his tool cart down Ridge Pike until it flipped over and smashed into the bed.
Ahh.. The good ol days.