Ok back from the vets office she found no obvious evidence of sacrophytic mange(so no reason to scrape), ruled out C. mange since these are three healthy older dogs she has followed for years. She also agrees 3/3 dogs with similar symptoms and our 2 months since last Topspotting probably should be ruled in as the cause so we will treat them today and then monitor. We also gave the neighbor enough to treat his three unvetted dogs who sometimes come under the fence to be pinned down by mine to hopefully remove that vector of potential transmission.
EDIT- OH, and praise whatever entity you worship this visit was only $40- woohoo!