The current system is twenty years old, the vendor has stopped meaningful development, the reporting is a nightly export into spreadsheets, and everybody agrees it has to go.
Then the project starts, and eighteen months later it is over budget, the go-live has slipped twice, and the controller is threatening to resign.
Construction accounting replacements fail more often than most enterprise projects, and they fail for reasons that are visible before implementation begins.
Why these projects are unusually hard
The system touches everything. Job cost, payroll with union and prevailing wage rules, accounts payable with lien waivers and retainage, billing with schedules of values, equipment, purchasing, subcontracts. There is no partial scope that delivers value; a contractor cannot run half its accounting on a new platform.
The rules are genuinely complicated. Retainage, certified payroll, multi-state tax, union fringes, joint checks and progress billing are not edge cases in this industry; they are Tuesday. Every one of them has to work on day one.
And the people who understand how it currently works are the same people who have to keep the business running during the transition. That capacity constraint is the real limiting factor, and it is almost always underestimated.
What decides the outcome, before implementation starts
A named business owner with authority. Not the IT lead, not the vendor's project manager. Somebody inside the business who can decide that a process changes and make it stick. Projects without one drift, because every configuration question becomes a negotiation.
An honest data decision. How many years of history move, in what detail, and what happens to the rest. This decision is where cost and duration escape most often. "All of it" is a very expensive default.
A written decision about process change. Either you adopt the new system's way of working, or you configure it to match yours. Both are defensible. Not deciding produces the worst of both: heavy customisation, arrived at accidentally, that makes every future upgrade painful.
A real assessment of internal capacity. This project needs several of your best people for a meaningful share of their time, for a year or more, while the business continues. If that is not available, the schedule is fiction regardless of what the plan says.
A contract that ties payment to outcomes. Implementation quotes are estimates and estimates get exceeded. Milestone-based payment tied to demonstrated function, with a defined change control process, is the difference between a partner and an open meter.
The pilot that is worth the delay
Before committing, run the hardest real scenarios through the proposed configuration. A certified payroll run with actual union rules. A billing cycle on a real schedule of values with retainage. A month-end close.
Vendors demonstrate the easy path. Your business lives on the hard one. Two weeks spent proving the hard cases is the cheapest insurance available on a project of this size.
Sequencing beats scope
The contractors who come through these well usually did less at once. Core accounting and job cost first, proven through a full close cycle, then payroll, then the surrounding modules. It takes longer on paper and finishes sooner in practice, because each phase is recoverable.
The ones who go live with everything on the first of January are the ones telling the cautionary story a year later.