I would recommend osquery as a free/open source substitute that may be deployed relatively easy and allow you to gather plenty of high quality telemetry. I've success story with it deployed to medium-sized company (20k workstations, 3k servers).
Keep in mind that you will need to implement monitoring based on data produced by EDR and corresponding incident handling. This is more difficult than paying for software and deploying it to your assets.
Keep in mind that you will need to implement monitoring based on data produced by EDR and corresponding incident handling. This is more difficult than paying for software and deploying it to your assets.