At GrantTree, I've had the opportunity to see a great salesperson at work (my cofounder!). The difference between having such a person on board and not having them is dramatic. It's make or break, for a business whose bread and butter is selling a productised service like R&D Tax Credits.
That said, having such a salesperson on board as a founder, and duplicating them (and therefore scaling the sales side of the business) are two different propositions. The second one is as hard - and as essential, if you want to grow - as the first.
The danger, for a small startup, with hiring a salesperson when you don't know how well they do, is that you might end up hiring the wrong kind of salesperson, one that's not adaptable and aggressive enough to get the sales in the loose, uncertain, indeterminate environment of a startup.
A good way to assess if he has these skills is to test this through the interview process. Just as in technical interviews you would expect a candidate to write code to provide his technical chops, asks the candidate to develop a sales plan if he were hired. But unlike a technical interview, give the candidate a few days' time to come up with a plan. This will involve researching the market, doing some preliminary analysis and would require some back and forth for the candidate to understand how your product would fit with the market. This is also a great filter for weeding out the uninterested who are looking for a â€˜job' rather than something more purpose/mission driven.
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