Own investment willingness
Applying for funding is no gold mine. No matter how much investement you attract, you need to put in many hours and resources in the project yourself. Therefore it's crucial that the idea for a development project is based on a real need in the market that in the long run will make your own risk and investements worth while. Many funds also require about half of the project sum to be covered by so-called self-financing, meaning that as an applicant you are willing to invest in the project yourself and thus share the risk associated with the development. Therefore it's important to have an idea of the project’s approximate scope early in the process so you know what you are engaging with. You don't need to fill out a detailed budget but simply collide some estimates on time consumption, hourly rates and external costs, e.g. materials, expert consultancy, production costs, etc.