So three days at your day rate, plus expenses, plus 2 days travel time, which I would charge half rate so that would take it to 4 days. My day rate is $1500, so for me it’s $6000 + expenses, which I would book myself. Since others also say it smells of scam, it’s most likely a scam. Unless you are a world famous photographer and she has way too much money there is no reason for her to hire you instead of a photographer at the destination. If she is local and you can meet with her to discuss it all and get paid the deposit in cash or EFT after the contract is signed then sure, maybe she does just have too much money, but if she is not local then I would be very wary of dealing with her.

More, larger lights to make things as even as possible. Distance to the background as well. Having it 2 feet back and having it 6 feet back makes a big difference. I used to have a 20x20 infinity wall and it was great for no shadows on the back.