The solution is cheap.

Icinga is a free open-source solution, but you can pay for support. We don't need support because my colleague and I are skilled and experienced with the solution. We also have a consultant who knows more than us. We call him if there are any problems. 

If you need professional support, you can buy support from the vendor.

The solution is free to use. Commercial support is however available on icinga.com.

The solution is free to use. 

We're using the free version of Icinga.

If you are using Icinga for personal use, you can install it without any additional fees. However, for organizational purposes, there are licensing considerations based on the number of users and the features required. So while the core Icinga software remains open-source, additional features and user support might have associated costs.

I wasn't involved with the finance side of the product. I just tested the product and gave feedback to the IT team in our company.

This is an open-source solution with paid support.

Even though Icinga's financial cost is low, it is an expensive product regarding the resources required to maintain and operate it. You need to maintain it and develop some probes while its deployment is manual. When you want to make modifications, such as adding new assets to be monitored or modifying the config file, it must be done manually without any automation or detection.

We do not have any licensing costs. 

Icinga2 is free, but you can sign a support contract with the vendor.

It is relatively inexpensive and may be okay if you are a smaller organization concerned with the price more than the utility.

It's an open-source solution.

Very reasonable.