Transactional costs associated with providing professional services are reduced by allowing prospective patients/clients (bidders) and professional service providers to negotiate competitively for desired fees for proffered services through an interactive on-line communications network such as the Internet. In an exemplary arrangement, a transaction system includes a communications network server that interfaces and communicates online with client computer systems belonging to various prospective bidders and personal medical service providers using, for example, an exchange of HTML documents and/or JAVA script applets. A service feedback interface and database are provided for handling online feedback information and comments from patients/clients and providers regarding the complexity and quality of services received or provided. A procedure complexity rating value based on concurrent personal medical problems/pre-existing conditions known to the prospective patient is defined and posted online.
