Section for customers to select a package and then to make monthly payment

I run an SEO company. I have 5 SEO packages for my customers to choose. Your role is to develop the stage from:- - selecting the package that suit the web visitor - a page for the web visitor to enter his BASIC details such as website, target search engines and keywords for SEO purposes - then lead the web visitor to select either a monthly automated payment page or a one-time yearly payment at a discounted rate -then lead the web visitor to make payment. Payment will be via Paypal. Then I will receive the above information accordingly. The entire thing will be an online experience. Your role is to develop that section. My website is built using Wordpress. It is completed, except for this package and payment page. You would need to ensure that it is working and the page is well-taken care of. To work with me, I will only pay you a 50% initial milestone. Please do not request for 100% as I do not believe in paying upfront even if you have more than 300 reviews. I do not have a tight timeline, but would need your commitment to complete this job.