Prescreen through email/phone and then interview a few. Choose the best family for my daycare then offer the space. I would not interview a family that doesn't need care for 6 months from my start date unless they are willing to pay for it until they need it. But, I would hold a space open a little longer for a really good family if I didn't have any better families to fill it. You don't want to waste your time interviewing anyone and everyone BUT at the same time you don't want to rush to fill it with a family that really isn't compatible with you and your daycare.