Other question is that he is going to spray and then roller it back over. Is that ok to do with Aura?

It is OK with the paint, the painter needs to be questioned on his (or her) experience with the product

He said he has used it before. What was interesting was he only uses BM products and when he went through the house he thought Aura was overkill, and to go with an eggshell from a less expensive line.

I should mention that the house would be completely empty while he is painting.

What I like most about the Aura is the washable finish. If I could afford any paint I would for with F&B, but that means the paint for my house would be like 5k plus labor.

It is you're home and you're $$, He should do what you want, no questions asked.

The quote I got for 5k feet above grade with paint is $8500.

That includes all supplies, removing a small wall paper border in one room, two coats and some plaster work. The paint would be Aura and he said it is 40-45 gallons.

That quote seems high to me. However it is in the NYC area.

What do others think?

Again, without seeing it , it is hard to say

What does 5k above grade mean???

40-45 gals of paint seems like way too much if no ceilings are being done

Get some more estimates.

I have an 1889 stick style and I have been very happy with Valspar's historic colors line at about $25 a gallon (Lowes) (I don't know if you are just painting white, or selecting colors that coordinate with tile/stained glass/light fixtures.)

My rooms are about 15' square with many pocket doors/doors and windows. I use less than 2 gallons of paint and 1 gallon of primer per room.