MB here. I give priority to a referral from another family, especially if it's on a neighborhood listserv or a parents group that I'm in.

The more anonymous the forum, the less weight it holds, but if a neighborhood family or someone I might know in some way feels positively enough about a nanny to publicly recommend them it carries real weight with me.

I always post my own ad. I think it shows a lot about how independent I am.

I know families who have posted Ads for their nannies because they feel bad they let them go but not bad enough to keep them around.