Trust me, almost every other buyer of an average consultant doesn't know what else his/her consultant can do... Most of the times your buyer is misinformed by the reference source... and sometimes your buyer jumps to a conclusion about consultants “specialty,” And this simple misunderstanding is the single major reason that an average consultant always remains the average, whereas top consultants drive eye-widening luxurious cars. So you should sophisticatedly reveal all your services before your client now and then... and ezines (newsletters) work like a charm in making your client aware here.