Local phone numbers.
Your business will receive a unique local phone number as your Google My Business call tracking number for every location you own, no matter where you are in the world.
Own your call tracking number.
Your Google My Business call tracking number is your property. No matter what. You never know who is going to save your number in their phone. Keeping that number active forever is important, even if you decide to cancel your ASAPmaps subscription.
Name, Address, Phone (NAP) consistency.
Citation inconsistency carries the risk of ranking penalties but today it's safe, and even recommended, to use a Google My Business call tracking number on your listing. Your real business phone number will still be listed as secondary in your listing.