Hi there, @Kron98. And congrats on landing a client!
For something like you’re describing, I typically do a fixed price with the scope of work detailed in the contract with the client. In your contract be sure to include the hosting/website maintenance fees (if any). In my fixed-bid contracts, I require 50% upfront and 50% on completion.
For creating contracts and sending out design/dev invoices, I use And.co with Stripe.
For hosting/maintenance fees, I use Webflow’s built-in client billing tool so I don’t have to foot the bill up front.
As for what to charge, every person in here might charge something different. It’s up to you, your level of design/dev, and ultimately, the scope of work. Some questions to ask when you’re considering your price point:
Are you providing SEO services to this landing page?
Is this a new business that also needs a style guide/branding included?
Are you doing the copy?
Hope this helps a little, and good luck with the build!