How do you finance your start up? Do you have another job or do you use savings / investments?

I bootstrapped FAM - Social Finance (coming soon launch) by working as a real estate agent. I wouldn't recommend it unless you are already a real estate agent, haha, but you happen to be; the flexible hours work well around sync-up meetings and other requirements of a start-up founder. On another note, I recommend that your first company be something you can prove the concept for with minimal time/funds. That way, you either fail fast and move on to something else or become a good candidate to raise funds quickly. Goodluck!

To begin with, I combine a startup with another job, but then I plan to look for investments. Without them, in my opinion, it is impossible to develop effectively.

First of all, I minimized taxes on investments. And it was a smart move. I've looked into Tax-Optimized Investments https://interactive-wealth.com/s... And it's helped me keep more of my returns. Experts in this area specialize in tax-efficient strategies. More information can be found here.