Q: How many woo commerce stores can sku grid connect and reprice?
A: Are you referring to woocommerce stores that you're hosting yourself? If so, then you can technically set one up about 20 of them and use them with 1 Sku Grid account. You'd just have to set them up as different country woocommerce marketplaces. So for example, if I had 3 woocommerce stores -- I'd configure woocommerce US for 1, woocommerce UK for another, and Woocommerce DE for the third even though they may technically be on the same country.
However, if you are referring to creating a free woocommerce website with woohosted to use for eBay repricing (WooHosted = WooCommerce eBay Sync), there's only 1 per sku grid account.