The short answer
Before buying business software, ask whether it does exactly what you need, whether growth is a setting or a project, whether the vendor is reachable, whether reports still need building by hand, and whether the data stays yours. One "no" is usually where the hours go; two or more mean the software will cost more time than it saves.
1. Will it do exactly what you need, not just what the product allows?
Demos show the product at its best. Bring one real, awkward case from your business (a return, a split delivery, a special approval) and ask to see it done, start to finish.
2. Is adding a plant, a location or a product a quick setting, not a month of work?
Growth should usually be a change in settings, not a new project. Ask exactly what happens, and what it costs, when you open the next branch.
3. Can you reach the company when you need them, not only through a ticket queue?
When something stops on a busy day, a ticket queue is not support. Ask who you will speak to, and agree response times in writing before you sign.
4. Does the management report come straight from the system, with nobody building it by hand each month?
If the numbers management needs still come from an export and a spreadsheet, the software has not solved the problem that usually matters most.
5. Is the data yours, during the project and after it ends?
You should be able to take all of your data out, in a usable format, at any time. Ask how, and get it in writing.
If the answer to any of these is no
One "no" is usually where the hours go. Two or more mean the software will cost more time than it saves. That is fixable, but it is far cheaper to find out before you buy than after.