Custom made software is per definition a bad alternative.
You have to map user requirements, think out a suitable solution, describe it in a functional design. Based on the functional design the software will be build and technically tested followed by the acid test: the functional acceptance and training of the end users.
In the end, you have to make sure that everything keeps operational during upgrades and changes with interacting applications and platforms.
In short: It requires effort that is not, or at least much less, needed when using standard software.
Therefore make sure you have an overview of what the standard functionality has to offer. Even if you know on forehand that it does not cover all your requirements, it adds to the picture of your own requirements.
In case the conclusion is that custom software development is needed, feel free to read further what our approach is and the added value of the open source paradigm.