There's a misconception that actually plays in your favor here: most people dramatically underestimate the execution risk of building a new product, particularl

There's a misconception that actually plays in your favor here: most people dramatically underestimate the execution risk of building a new product, particularly software. If you can communicate very clearly what the product is going to look like and what it's going to do, selling a product that isn't done yet is not much harder than selling one that is. In some ways it's easier, because the customers can fill in the details themselves, and they don't appreciate how hard it is to get all those detail right.