Just thought that I would share this... I'm currently in a consulting nightmare... I'm doing some consulting for a very large client and they have over 200 different applications scattered all over the place ranging from Mainframe COBOL systems, C#.Net, Some proprietary garbage, Sharepoint, Java, classic asp, VB, C/C++, and numerous mobile apps, with data stored in about 40 different sources including DB2, Flat files (.txt, .dbf) SQL Server, Access, thousands of pages of excel documents, and Oracle.
90% of these systems rely on information from each other and integrate into each others databases with numerous batch jobs and ETL jobs that move crap around at random, yet every single application that may accomplish one sole function relies on the outputs of potentially a dozen systems including systems located with international companies. There is no documentation present describing their systems architecture, my mention of UML and BPMN terrifies them, and the oldest business architecture documentation is from 2000, the result of a failed Siebel and later (failed) Oracle BPR.
That's the idea... but when I took on this consulting job as lead I didn't think it would be this bad. This is by far the biggest mess I've seen at a company... and they really don't seem to think there's anything wrong. The only reason they are pushing for this change is the COBOL developers are dying off and there's no one to maintain their crappy core system lol.
You might have to tell them that, quite simply, you didn't bargin for this degree of horror when you hired-on, and tell them that they will have to find someone else to handle it.
You might also remind them as you leave that their system is such a mess that it will cost a lot of money to fix it -- but it will cost more to drag it on until people start dropping them as their provider.
Sometimes, as consultants, the advice we have to give is simply, "I didn't hire to dink around with a broken system," or some like thing.
There will definitely be takers as long as that company is willing to fork out the monies. I had the opportunity to work for a company that is in the transition of a failed system project. When I join the project fail on performance and it was getting into a law suit between my company and the vendor. Imagine you are asked to maintain and support that system!!!
A call for tender to salvage the system have takers definitely. But they are "smart". They prepare two proposals. One is to salvage and the other is to re-built from scratch. Guess the costing ? It is *CHEAPER* to re-built from scratch than to salvage. That vendor is not rejecting the idea of salvage but indirectly using the quotation, they are advising my company to choose wisely.
So yes trying to salvage or maintain such systems is very difficult but still there will be takers given enough time and enough monies. I believe for your case, with enough monies throw out it is no difference. You not taking it others will. Ain't this world is all about ?