The most time I ever spent on interviews HR phone screen, then phone interview with hiring manager (supposed to be quick, but was over an hour), the in-person interviews with 3 people was supposed to be 1.5 hours, ended up being 3 hours. Then another round with senior people for another 1.5 hour. After the offer, a follow up call to clarify some responsibilities. Ended up being 7 hours total with 5 people. Recommend getting clarity on your responsibilities if you get an offer.