We are able to set up an online store for single items usually with hours. We often use Stripe as a payment gateway (see the review of Stripe) on the websites we create. But now that Square (see the review for Square) has joined as a payment gateway option as of late 2016 and several of our clients already have integration with that company, it only makes sense to utilize Square. The benefit of having a payment gateway is that you will not be offloading traffic to a third party website like PayPal where the dropoff rate is higher. An SSL (secure socket layer) certificate will be needed for your website in order to have a payment gateway and an online store. However, nowadays this should be standard anyway. Multi-item e-commerce websites can take days or weeks to be completed depending on the number of items and the content that will be added to your site. We do offer a database import service if you are a reseller of items.