The major challenge with cross browser testing is setting up the infrastructure and its maintenance.
Since cross browser testing requires testing of a given website on different mobile and desktop browsers, browser versions, operating systems so it becomes next to impossible to have these thousands of combinations and to maintain them.
It also poses monetory challenge for SMB along with infrastructure limitations.
The best way to overcome this challenge is to use a cloud based testing tool that does the maintenance of infrastructure for you. All you need to do is to login and use on demand machines as per your needs.
And pay as you go! Just pay for your requirements. No taking care of updates, licenses, thus saving you from a lot of headache. One such tool is LambdaTest.
Just create an account, login, and start using any of the combination, browser, browser version, resolution, mobile, desktop.