Hello! I have read your requirements carefully.
An online store can be built upon several platforms and we have a plethora of choices these days. Most single vendor stores can be completed within a budget of 2000 USD, but if we are looking at a magento 2 based platform than cost can reach 2500-3000 USD.
The major requirement from your end would be a product catalogue. Please note that listings and creating variations for your clothes are not included in the development cost as it will be an ongoing part of your business operations. I will, however, train you in managing the store and if you wish we can also manage it for you if there is an annual contract. But I will definitely list some sample products.
You will need to have a payment gateway service,
A shipping service provide
A domain name
A hosting service
I can guide you through all these requirements if needed.
For further discussion and free consultation, kindly drop a message. Regards!