Section 206. The preceding section shall apply to all persons engaged only in a local express business for the forwarding of express matter between points within the commonwealth in the trains or cars of any railroad corporation, and to persons desiring to engage therein who obtain the recommendation of the department therefor, and who agree in writing to indemnify the corporation against all loss of and damage to any property carried by them on its trains. Such recommendation shall be given only after notice to all parties interested and a hearing thereon, and with regard, among other considerations, to the public interest. Such corporation may contract with one or more persons for the express service over its railroad or system, subject to the rights of such persons as may then be engaged in, or shall have obtained the recommendation aforesaid to conduct such local express business thereon between points within the commonwealth under this section; and the terms, facilities and accommodations provided for such last named persons shall not be unreasonable or unequal, having regard to the amount and character of the service and also to such reasonable regulation of said business as may be for the public interest and the efficient operation of the railroad. This section shall not deprive any railroad corporation of any right which it has under its charter or under general laws, to perform all the transportation of property upon its railroad.