Vendors quote timelines assuming you respond instantly and decide quickly. Here is what the same project looks like with realistic client-side effort built in.
| Phase | Duration | What your team does |
|---|---|---|
| Discovery & scope | Week 1 – 2 | Walk through every workflow; sign the scope |
| Configuration | Week 2 – 4 | Supply masters, fee or price structures, templates |
| Build & review | Week 3 – 7 | Review at milestones; approve or request changes |
| Migration & validation | Week 6 – 8 | Clean data; reconcile and sign the report |
| Training | Week 8 – 9 | Release staff for hands-on sessions |
| Parallel run | Week 9 – 10 | Operate both systems and compare daily |
| Go-live & support | Week 10 + | Switch over; raise issues in the first close |
Where it slips
- Scope sign-off. Waiting on a decision maker is the most common two-week delay in the whole project.
- Master data. Item and customer lists arrive incomplete, and building around gaps costs more than waiting.
- Staff availability for training. Book it in advance. Training squeezed into a busy week does not stick.
- Scope creep during review. Legitimate, but every addition moves the date. Decide whether it goes in phase one or phase two.
Choose the go-live date carefully
Go live at the start of a financial period, never mid-month. For schools that means a term boundary; for trading businesses the first of a month or quarter. It keeps opening balances clean and gives your accounts team one clear cut-off to reconcile against.