In terms of biz-dev I'm happy to share, because it's been the definition of doing something that doesn't scale, but it's worked to this point. When we were getting started, our team + family and friends split up the task of pinning independent coffee shops on Google Maps, by using keyword searches like "local coffee," "espresso," etc. From there, we'd profile these locations by documenting their phone number and then searching the web for an e-mail address and (preferably) an owners name.
Once we had those email address, we'd setup sales campaigns to anywhere we had an e-mail address to - we still do this today.
In terms of our approach at scale, we're hyper-focused on partnerships and reputation. 1) partnering with company's like Square, Odeko and a number of roasters has allowed us to find customers in existing channels, avoiding the need to deploy a massive sales team (that requires egregious funding) to knock on doors 2) reputation is everything in coffee, and the more customers we add, the more referrals we get from existing locations.
Because we support a single vertical, having a few customers that love our product and are willing to voice that praise has gone a long way - our goal is to continue facilitating that level of enthusiasm, in order to grow.