Congratulations!
Unless she is very wealthy, she can't afford all of that. I have known several friends to sell kings that cost over $1,000 and queens aren't much less. Yes, I know it depends on design, materials etc., but it is not cheap to make quilts and you may be tempted to sell yourself short. This is a lot of work. Also, sizes mean different things to different people. Some people want quilts that are more like bedspreads. Some people want quilts to hang down a certain length below mattress. Mattresses come in different sizes now and the depth of a bed can affect how long or short a quilt is. Batting can also be a factor. Some people think they want thick batting, others don't care about batting. Batting in the north can be different from that in the south. Batting costs should be considered. These details are important to come to an agreement about before a price is mentioned.
You need to consider if you are going to have someone to quilt the tops for you, you need to know how much to charge for that. Prices may go up before you get it quilted. Time deadlines are another issue, and check with your long-arm quilter to know deadlines for submission, particularly for holidays. If you are quilting it yourself, don't sell yourself short just because you are doing that.
You need to have a written agreement. I collect 50% up front (cover materials in case the person bails on you). I would handle each quilt transaction separately. You need to allow yourself extra time in case of illness or an emergency.
Consider type of payment. I take cash or PayPal. There are fees involved with PayPal, so I know that and make sure my price covers that type of thing.