Mixed use 4-plex Questions

[Conner Smallwood]

So a mixed use 4-plex with 3 apartment units and one storefront unit. 
1. Would this require a commercial loan rather than a conventional because of the storefront unit? I know that 4-plexes generally can use conventional.
2. Could the storefront be converted to another apartment unit? It wouldn't be "mixed use" after that.