We operate a wholesale food distribution business between Lille and Brussels. We commissioned a software agency to build a custom web application for 28,000 EUR to manage our internal orders, accounts, and dispatches. Testing is done the project went live, and we signed the delivery acceptance report last month.
The agency has now proposed an ongoing TMA (Tierce Maintenance Applicative) contract for 850 EUR per month. The proposal mentions corrective preventive, and evolutionary maintenance. But paying a fixed fee every month for a brand-new system that we already paid for in full feels like an unnecessary cost for our budget.
What exactly do these TMA contracts cover in practice, and are they really mission-critical for a small business with a newly completed project? If we decide to sign, what traps should we look out for regarding SLA response times and rollover of unused hours?