FICO credit scores aren't intended for tenant assessment - it's just a lazy option some landlords do. The credit companies have dedicated products for such a use case (https://www.mysmartmove.com/).

Realistically, paying off a loan rarely hurts credit scores. And realistically, someone with years of paying off credit cards on time is going to have a high credit score (at least high enough for things you describe), outstanding debts or not.