As a seasoned financial modeler myself, I'll say that it is important for someone in my position who's lacking relevant industry experience to partner up with another professional modeler or industry executive/advisor who does have enough relevant experience and insights to shape your financial model with the right logical structure and reasonable, valid assumptions.
A financial model is FIRST a tool for testing your business model assumptions and running scenario planning exercises to validate the viability of your business model under different potential circumstances. If you're going to use it as a tool to raise capital, it is also means for communicating to potential investors that you thoroughly understand the individual activities that you plan to carry out in operating your business, the interdependence of those activities, and the expected financial results, cash needs, etc.
In addition to checking with your friend's reference(s), I'd recommend that you ask them to walk you through one or more sample models they put together in the past so you get a clear understanding of what their work product will look like, the level of detail they'll go to in developing your model, etc.
Message me on LinkedIn if you'd like to discuss further!