I no longer keep a wait list as it was getting too long and when a space opened, I'd be emailing people who needed care 6+ months ago in some cases. They had obviously found other care so it was a lot of wasted time! I now just tell parents that I'll post on my dc fb page and they need to keep an eye on that. I do still keep their messages so when a spot opens I can go back read them and contact only the ones that I think will be a good fit in regard to timing and age.
When I interview, I schedule one at a time. I meet the family and if I like them, offer the spot and give them 2 days to decide. If they want it, great! If not, I schedule the next family and do the same. I used to interview multiple families but than would have a few who were a good fit and I'd have to decide who to pick and say no to the others which doesn't feel good. This has cut back on that AND also cut back on my interviews as I now only have to interview 1-2 usually which means less wasted time!!