There is no perfect solution! The good news is that there are numerous options available, so you can find a price that fits your budget. Check out our Best Ecommerce Platforms Review, which includes website builders like Wix and Weebly, if you want to sell online for $20 or less.
Shopify starts at $29 per month for dedicated hosted eCommerce solutions, and BigCommerce starts at $29.95 per month. Because hosting plans vary so much, self-hosted solutions are much more difficult to calculate.