I've started operating in really granular units of work. Like less than $1000 per. Cash on delivery. This won't work with all clients and all jobs, but there are places where it does work very well. Advantages include being able to avoid paper contracts altogether. Verbal agreements and a 4 column xlsx that is reviewed monthly are all that seem to be required with some of my clients.

If I don't get paid for one day of work, I will probably get over it in a few hours. If I don't get paid for six months of work, we will have a serious problem. The tighter and more incremental we can make the delivery process, the less likely anyone gets screwed.

If a party is pushing hard for long-term contracts or large up-front sums of payment, I would walk away from that transaction unless there was a literal golden goose sitting in their lap.

I am also trying to set granular milestones and get paid every 1000€. Not provide 20000€ work and then start looking for my money. I can live with a loss of 1000€, but missing 20000€ will impact negatively my mortgage and investment plan.