Most Sage 50 and Sage 200 migrations don’t come unstuck on the software side. They come unstuck when finance stops trusting the balances while VAT returns, bank recs and board packs still have to go out on time.
Our write-up sets out what actually moves across (customers, suppliers, nominal codes, dimensions, opening balances, plus however much transaction history you decide is worth paying for) and why proving those figures against the old system before cutover matters more than the go-live date itself.
It also covers realistic durations by project size, a sample eleven-week schedule, indicative UK budgets, and a table of failure modes with the fix for each: messy nominal codes copied straight over, no formal sign-off from finance, customising before anyone has tried standard functionality, and training left until after users are live.
Worth reading even if you land on “not yet”. There’s a section on when staying on Sage is the sensible call.