website to accompany my book - for advertising and subscribers

My project is to create a website that showcases my book and supports online sales. I have an existing domain available and plan to monetize the website. The primary purpose of the website will be to highlight the book and also provide useful information and updates to my subscribers. Additionally, I need the site to be optimized for search engines as well as mobile friendly. I am looking for a developer with experience in this area to help me create a functional website that looks great and works well. I need someone who is not a "cookie-cutter", one-size-fits-all designer. The webdesign needs to reflect the tone and energetic of my book, which tells the journey of my life to find a personally meaningful spiritual path. The selection of font style and size needs to reflect that. I will attach the cover and back cover text )if they fit) so the designer can get a sense of what the website needs to convey. I want to be able to add files periodically. I am an 85 year old woman who is self-taught on computers, but I'm pretty astute in technology for a person my age. I need the website to be USER-FRIENDLY both for me and my subscribers. I don't want it tied to an ongoing cost I have to pay for someone else to maintain it. I also need the cost to be under $500 - preferably less, since it has already cost me $27,000 just to get to this point! Lastly, I want to see some samples of the proposed web designer's prior work that would be transferable to my genre. Thank you for considering my request. Anne Bruetsch