Do it now. Yes, test that idea of yours by doing it right now. Too many times, you’ve thought of a brilliant idea and then contemplated various scenarios and how it could all play out. You’ve analyzed every possible aspect of it and tried to guess and estimate all the contingencies. Then, you’ve discarded it without properly testing it out to confirm if it would work or not. I’ve been there.
Though this is needed to some extent, it’s not the best approach. The best way to confirm if something works or not is to start building it, and testing it. Brainstorm a very quick way to put together the most basic form of your product, and send it out to potential customers to test it. This process will result in the best estimates of how the product might fare in the real marketplace, and it will provide you with real feedback that will help you polish your idea, and create the necessary improvements.
With the limited resources you have, do it now, and test it now. The right time is now. Starting out small is the best way to test something that can grow into something big.