A few inches; I don't know the exact measurement. The first pic gives a good idea, except he ended up going even lower and he started well inside my hairline due to thinning.
This was the night before, note the small mole slightly left of centerlinr of my face.

This was just a little while ago, the mole is now much closer to my hairline.

If you look closely at this pic, you'll see a black line inside my hairline. That's what became my new hairline, once he lowered it just below the lower black line. 2-3 inches maybe?

I'm really glad I went to Mayer. I'm real life friends with Riya and Vanna, and love how he worked on them and also his aesthetic sense matches mine.
A few weeks ago, I let a friend drag me to a second consult with Dr. Deschamps (as I live in SF), and I did come away impressed. He and his team are incredibly professional and detail-oriented, and from the work of his I've seen in person he may very well be better than Dr. O ever was.
The only real disconnect with him was he seems to be incredibly aggressive in his work while I was looking to be more subtle, and he also wanted to basically rebuild my face for 53k. Now I can afford that, but while I was unhappy with my face I certainly wasn't 53k worth of unhappy, So I ended up still going with Mayer. Deschamps is still an excellent option for someone wanting or needing aggressive work and a type 3 forehead reconstruction, but he simply wasn't a match for my goals and desired result.