Nanny share - split days

Hi everyone,

My husband and I are expecting our first child at the end of this month and starting to plan for childcare in the fall. We're hoping to begin a nanny share around September, when our baby will be about 3 months old. Ideally, we'd love to find another family to split the week with, since we only need care three days a week. We can be somewhat flexible on what three days those are. 

Is it common to do a nanny share where the families split the days instead of doing full-time together? If anyone has done this, we'd really appreciate any advice on how to make it work and recommendations on how to find a compatible family. 

Thanks so much in advance!