Take a look at both Drip and ActiveCampaign.
Both feature integrations with tools like Shopify, BigCommerce and WooCommerce. Both have nifty ecommerce-specific features, such as abandoned cart emails. And you can get both starting at $50/month – that’s certainly a lot cheaper than HubSpot.
In fact, I would only advise HubSpot if you’re in B2B and really are a newbie when it comes to marketing automation – their tool is easy to use and looks gorgeous, plus there’s a ton of training videos in there.
For everyone else, that’s able to figure a little bit more out themselves, the two tools I just mentioned are viable alternatives to HubSpot that offer comparable functionality (and sometimes downright better functionality, and integrations, too) at a much more attractive price point.
I first answered this question on Quora: