Good afternoon. I need to develop a custom web application, what can you advise? Is it expensive? It's probably better to look for reliable developers right away.

I think we should look for developers

If you want to get quality results, it is better to turn to professional developers. Or to study this question very well

This is a very important process, and you should approach the process of creating a web application responsibly. You can read all the necessary information https://clockwise.software/blog/how-much-does-it-cost-to-build-a-web-application/ if you need Custom Software Development and contact a good company, which will do everything quickly and qualitatively.