Aswan, whatever you do understand that it will have future implications because you are either introducing another class of shares (restricted) or an option plan, which you might want to have in the future for either contractors or employees (or maybe both). Either way, you have to protect yourself and the company, legally - meaning you have to "paper the transaction." And at this point your development (just guessing based on your comments) you certainly don't want to waste time or money on that. Why not just issue regular shares. I assume you have a shareholder agreement. The contractor shares would be governed by the same agreement as all of the other shareholders.
This is the good news, bad news associated with using your equity to pay for services. You're conserving cash, but, you're bringing new shareholders into the fold.
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