You can make any business or work 100% Halal. Islam is a practical religion and it never talks a hypothetical thing.
Whereas you said that in working environment if you are receiving any personal call so it becomes Haram but the question is has your employer placed this condition that you do not have to receive any personal call.
Secondly, how do you interpret that if you are receiving any call for the company but you are greeting on personal ground. Here, I must make it clear if you have any doubt on this ask your employer that whether if you receive any personal call is that okay or not. Secondly, if your phone discussion is really taking good time that affects your working hours or your attention on work. Then you need to think on this as this is affecting your purpose of working in that institution which may become Haram depending on the situation.
Second question of business, why should you sell bad or duplicate things in the name of good thing? This itself is Haram. Quran curses those who cheat. You have no right to cheat. You can sell a genuine thing and take the reasonable profit. There is no need for false statement.
Syed Aon Naqvi