Number of branches to open

No, your friend cannot legally open 4 new branches in different cities more than 60 km apart as a sole proprietor with just regular staff. Under Section 27 of the CA Act, because the distance exceeds 50 km, each branch must be under the separate charge of a qualified CA member of the ICAI. To do this legally, your friend would need to hire full-time qualified CAs or convert the proprietorship into a partnership firm with partners stationed at those branches.