Best way to find cell phone number?

[Henley H.]

Any suggestions as to how to get a current phone number for a property owner?  Feel like we've scoured the internet and also paid on various sites for information, such as Spokeo in Intelius- though we've found 6 different numbers, none of them are current.  We don't really have enough demand to warrant a skip trace membership, unless there is a reliable site that allows you to pay per inquiry-  Any ideas appreciated!