From the time you start until the time the system is live, expect at least a full year to transpire. This is our gut feel for most turnkey sites. Turnkey systems generally should take less time than the other options. Customized implementations will take a bit longer as everything is checked out and verified. And, fully custom and unique systems will take the longest and require the most effort. It is also possible for unique systems to be designed, built, and installed in a year, but these will be the exceptions and not the rule.

It does not matter if the project plan says that the system will be installed in three months and that you will be running 100 percent live a month later, do not bank on it. There are some of these installation success stories out there, but they are few. The situation has to be amazingly simple and clean for such quick implementations. The target for system implementation might be less than a year and it is good to set such targets if there is some evidence that the targets are possible, that the vendor has done it before. Just do not be surprised that after false starts and some retreating and advancing, it takes a year for the system to be stable and useful, with constant handholding by the consultant or vendor. Even if a vendor has done a quick install in the past, are your data and situation exactly the same?