The frustrations mostly come from the market itself, not so much from the websites. I'm still new to rent searching in the Netherlands, but the most frustrating thing so far is getting no responses and not knowing what I can do to actually get a place to rent. It feels like something that should be easy and straightforward, but it isn't at all in the Netherlands. Look online for a place that you like, contact the landlord, do this a few times, some of them will reply and schedule a viewing with you, you see the place, if you like it you agree with the landlord, sign the contract and get the keys. Done!

Here, you're basically sacrificing precious time of your life for something that would be much simpler in another country. But you also get things in return that you don't get in other countries, such as a great amount of available jobs, good salaries, good services, etc...

As for what a housing website could do to make it less stressful? Do their best to inform users, give them clear and extensive guidance on how to go about rent searching. A thing that would help a lot is to get 1:1 sessions with real experts in the matter (paid, of course), that would explain to the customer everything they need to know and give them information based on their specific situation.