Woocommerce is free it is wordpress based, you can get nulled themes and plugins, but most of them it is free, it is more complex, but for start you need only domain and server.I`m getting god servers and domains for 20+ bucks on full years, if project successful I`m upgrading server for 100 dollars per years, but main thing that you have time and you don't have limitations in woocommerce.
in shopify it is different thing, you need to pay every month you need to pay every month $29 + domain, if you want to have Abandoned cart recovery, you need to pay $79 in month and they charge 2.0% if you use paypal or stripe per you salle, after that you need oberlo, because I think this is main power of shopify, main plan is free, but you can add only 500 products in month and make only 50 order in month, then you will not gonna get Shipments Tracking, Orders fulfillment monitoring and Multiple Users, without shipment tracking it is big chances that your paypal will be frozen and you will be in trouble... So there is other plans of oberlo, $29.90 / month, products per month 10000 and 500 salles, products is fine but salles I think it to small, then you have last plan $79.90 / month, 30000 products and Unlimited salles, so this means if you will bank hard you will need to pay shopify $299 + oberlo $79.90 in month.
At the end your shop will be in platform, so In my thought you will not have shop, you will just rent soft in their space that allows you to sell, after that you even buy domain in there... So about selling your shop in flippa idk, maybe it is possible you just pass acc to other person, but in woocommerce, you control everything and you have shop files inside server, database files and most special thing working in woocommerce you will get good experience, later if you want to get job or something you can say that you have experience in woocommerce, that you had shop or something.
And i`m in UK now, in UK first years is free for business, letter you can get self employed.
