Hello, I have experience in working with ecomerce platforms and can close this project as per your requirement.
Below is a brief of how I can support you
I am assuming that you are starting from scratch - no web address and hosting space.
I will be using a commercial grade service provider (I am not associated with them, nor do I work for them) that would charge you a monthly fee for hosting an ecommerce site. This service includes everything required for an online store - product catalog, shopping cart, payment gateway, order tracking etc. The monthly fee from this service is about $30 per month
Maintaining this site and expanding does not require programming skills, I can help you understand how it works and take it forward. I can also help you understand how SEO works and help you increase traffic to your site
I know I have quoted higher than your upper limit, but I can do a complete job of it, from design to your order closure. My milestone request is 50%
I have some questions
1. Do you have a registered web address ?
2. Do you have hosting space ?