You can set up Authorize.net integration from Settings → Add Ons → Enable Payments through Credit Card → Use Authorize.net.
Once you click Enable, you’ll be asked to enter your Authorize.net API Login ID & Transaction Key.
To retrieve this information, login to https://account.authorize.net. From the main toolbar, click Account → Settings → Security Settings → API Login ID and Transaction Key.
To generate a Transaction Key and API Login ID, enter your Secret Answer where prompted.
To learn more about disabling old Transaction Keys, click here.
If you have already generated your API Login ID for another purpose, you will not need to generate it again. It will be available on the same page, shown below:
You can now enter the ID and key back into EZRentOut:
Hit the Verify Account button, and you’re done. Scroll down to the end and click the Update button to save your settings.