That is hard to believe. By the time you subtract out a modest house, driveway and/or sidewalk you're talking about 5,000 square feet of grass. There are some guys on here who would fertilize and spray a yard that size TWICE for $45. Keep in mind the lady you have the $75 quote to may not have been telling you the truth about the other guy. Advice/opinion: I don't think it is smart or considerate to post identifying information about a customer's home on lawnsite. A couple pictures are fine, even the a aerial shot is ok, but showing the full address crosses the line IMO. If I were that homeowner and found this I would be hot whether you got the job or not.