On average we scalded at 145 degrees for 1:30, timed. Kept the heat on once we started scalding and checked temps with the biotherm every time. Didn't notice any real temp drop. Tested wing feathers to determine done-ness. I cheated on the plucking and dropped them in a featherman plucker. I also trimmed off the tail, instead of just removing the oil gland.
Been a hunter and worked in restaurants for 10 years, so I have had a lot of experience handling animals in the round and getting them table ready, so for a small batch I would say stay organized. Scald all your birds at once, pluck them all at once, then butcher and store. For the 5 birds, including set up and tear down of our outside staion, we were right at an hour. Easily half of that time was set-up and tear down.
Doing the chickens was actually easier than processing a duck or a goose.