License Key Whmcs ((hot)) Free Link
Until 2021, WHMCS sold for a one-time fee (~$300). If you find someone selling a legit owned license (transferable), you can buy it second-hand. Check WHMCS Marketplace for verified transfers.
Using nulled software is a violation of WHMCS’s licensing agreement and copyright law (DMCA in the US, similar laws globally). While WHMCS typically sends a cease-and-desist first, repeated infringement can lead to: License Key Whmcs Free
If you cannot afford $15/month for WHMCS, you are not ready to run a professional hosting business. Instead: Until 2021, WHMCS sold for a one-time fee (~$300)