Ask HN: How to build out a startup in the medtech space?

During my Master's I have built a working prototype for clinical documentation that could be universally used in multiple clinical areas. However I have very little experience in founding a company or talking to investors. I am based in Germany. And since the startup scene here still lacks a lot of funding I wonder what my next steps should be.

The university hubs are not an option, since they require you to hand over up to 45% of the company for only 100.000€-500.000€ funding. Given the regulations in the medtech market this money would not give that much runway. And looking in the future with multiple investment rounds I would end up with very little stake in the company.

I talked to my family and could collect 35.000€ in total myself.

I think the issue here is that this company would most likely not be a unicorn, or a fast growing startup that most investors look for. However, the profit margins are very large and the solution is very easy to scale. Thus the worldwide market is open at relatively little cost, compared to other solutions.

I already did market analysis, tested the solution with multiple clinicians, and my solution would cut the costs of clinical procedures (depending on the type of procedure performed) by up to 20%. I also have very positive feedback by the four clinicians that tried out the solution so far.

Four doesn't sound like much but it is very hard to get in touch with a clinical expert as a single student without funding.

I could really use some advice on my situation here. I am also looking for co-founder advice. How much stake should a co-founder be offered? I really do not want to end up only owning a fraction of the company in 10-15 years.

My personal goal with this company is to grow old with it.