Right now I'm working on the concept of minimum viable design - what is truly needed to get your business going and to the next level. First – make sure you aren't designing for design's sake. Customer acquisition is numero uno and that usually doesn't take a lot of design out of the gates to start selling. At any rate if you're not there yet – I've found paying for design always results in a better result than "equity". Your company isn't worth anything (yet) and as soon as something else comes along for your designer "partner" he could jump ship and you'll be hosed. I've always found people work harder for money unless they are an original co-founder or partner. Hope this helps!

Without a dedicated advertising budget, you're going to have to put in a lot of man hours with guerrilla marketing at first. I would create a quick 5-10 slide PDF highlighting the benefits of the service and the real value to your clients. This can be at the ready as a followup to actual conversations you have with prospects. Your biggest challenge will be teaching people about this new way to buy and so develop your sales conversations around combating that challenge. Is it easier? Faster? Cheaper? Safer? Think about what the normal process is and then position your product as a much better alternative. A good printed sales sheet could go a long way too!