All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.
Praise be to Allaah, Who has guided you to look after and work for the interests of Muslims in your community! There is no doubt that your efforts shall earn you a great reward from Allaah. Also, may Allaah reward you for your keenness to learn about the religious matters before you proceed with action!
You must know that you are not allowed to impose any charges on the people who are going to attend iftar gatherings at your center. On the one hand, this will cause the needy Muslims in your community to shy away from coming to your center even though they may be in dire need for help. On the other hand, this will open the door for fortunate people to attend your iftar in return for little money. Both cases will not fulfill the mission of your center and the objectives of your donors.
The solution is that you consult the businessman on deducting a sum of the money that he has donated and spending this sum on the services needed for keeping the place convenient and well-equipped for iftar. This is because the money that the businessman has donated should also cover the costs of preparing the place where the iftar will be served and securing the necessary needs, including food, water and electricity.
Allaah Knows best.