Based on the context and the answer, generate a question. 

Context: Real estate postcards are another aggressive tool to generate leads . This is a way to promote the name and services of a broker effectively to gain new clients . It is an affordable way to grab attention it is highly visible and easily tends to generate response . On top of that , the possibility of postcards being read over by prospects is almost a hundred percent . This is the immediate impact that makes real state postcards so effective in drawing prospects .. Another advantage of the real estate postcard is it 's by far cheaper , with no envelop to open and no paper to sort through .

Answer:

Realtor 's email address



What would be the best information that can be found on these cards ?