Great questions. Ecwid is a solid choice since it is free up to 10 products. It also allows you full control over it's CSS. It doesn't give you any control over the structure of the HTML however so there will be some limitation there. Since it is free you can sign up and give it a try to see if it will fit your needs. Another perk is that it can be embedded into Webflow.
If keeping your site on Webflow isn't a must, then Shopify and BigCommerce might be options. They give you full control over the HTML and CSS. They are more pricey but they do have free trials so you can take a look. You will have to get familiar with their template syntax; Liquid and PHP.
I am a Shopify and BigCommerce development and design partner so If you are interested in those options let me know and I can help you out.
It really depends on the features you need now and the features you think you are going to need in the future.
Questions to ask:
- How many products are you going to sell, how many categories and sub
- How many payment methods do you want to offer?
- What kind of shipping information do you need?
- What markets are you selling too and do you need to be able to sell
in multiple currencies?
- Support for Gift Cards, gift certificates, discount codes?
- Do you also have a brick and mortar store?
- If so what POS and inventory system do you use?
- What credit card processor are you going to use? (Paypal, Stripe,
- And most importantly are all the features above available in the
country you are operating out of?
Hope this helps you navigate the world of e-commerce,