You may want to consider offering multiple "packages" if you don't want to lose those clients. $3000/$40 = 75 hours... if you offer a package that's 25 or 50 hours, you can lower the price and maybe keep the client.
That said,
1. You have to set expectations clearly - if they're not paying for a $3k website, they're not getting a $3k website. (most people will still expect that quality even if they're paying less, for whatever reason) Be clear with them about what they're getting.
2. If you have enough work at that price, don't bother. My guess from you posting this is that you want their business.