Account and Contact Associated Fields Default Value - Work Phone Case

Hi everyone,

In our buisness case, 80 percent of Contact's Work Phone Numbers will be the same as the Account's Work Phone Number. Though sometimes because someone may have a direct line, a Contact's Work Phone Number will not be the same as the Account's Work Phone.  

I want to populate the Contact's Work Phone Field from the Account's Work Phone Field. This can be achieved by a JoinFieldValue Default, but when I use this route, I have to first save the Contact before the Work Phone populates. Therefore, the user can't review the number before the save. The user also doesn't know that the Work Phone will populate, and therefore the purpose of this automation is defeated.