website development

I am in need of a website to showcase my accounting services and connect with my customers. I am open to suggestions on what platform the website should be developed on, though I do have some specific requests. The main functionality of the website should be an online client portal, where my customers can log in and submit forms as well as view current accounts and payments. I would also like the ability to potentially have other features such as a dynamic calculator or a booking system in the future. It is important to me that the website is able to fulfill my clients' needs as well as my own. I am looking forward to seeing what creative solutions you can bring to this project.