Tips for selecting a SIEM/XDR/EDR

I've been thrown into the deep end after the only cyber security colleague left the company.

I've been in Cloud for a few years, but am now taking on a ton more security-related tasks since there's "no budget" to hire anybody else.

We currently have MDM, but no SIEM or EDR.
We have a remote workforce (Windows and MacOS) and small AWS presence (mostly Serverless or Linux), but our business depends on everything in the cloud.

Are there any must-have …

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