Off-the-shelf tools are the right call most of the time. They are cheap to start, fast to switch on, and good enough for commodity tasks. The trouble shows up later. The price climbs as you grow, you cannot bend the tool to your process, and your data lives on someone else's platform under someone else's rules.
A custom build costs more upfront and takes longer. What you get in return is a tool shaped around how you actually work, one you own outright, and one that keeps doing its job even if a vendor changes their pricing or shuts down.
Our rule is simple. Rent the parts that everyone has. Build the parts that make you different. Those are the tools worth owning, because they become an asset instead of another monthly bill.