Self Hosted Email Verification Software: Would you prefer ?

Curious to know if you would like to own a Self Hosted Email Verification Software with one time purchase & LIFETIME License . Most of us use a Email Verification SAAS to verify lists or individual emails. The cost is quite high. Couple of existing open source email verification tools are API only and verify only individual emails with no GUI & database support. I am working on a self hosted alternative to paid ones with bulk verification (own code, not existing open source code) & history feature. I don't want to reveal other "GREAT" features as of now.