No person, firm or corporation shall establish, maintain, conduct, or operate a mobile home park after April 30, 1972, without a license therefor from the Department. “Conduct or operate a mobile home park” as used in this Act shall include, but not necessarily be limited to supplying or maintaining common water, sewer or other utility supply or service, or the collection of rents directly or indirectly from five or more independent mobile homes. Such license shall expire April 30 of each year and a new license shall be issued upon proper application and payment of the annual license fee provided the applicant is in substantial compliance with the Rules and Regulations of the Department.