paul
there are only a handful of reasons why a company changes theor cleaning supplier
1. service
2. price
3. just fancies a change
there may be more
unfortunately you need to point out to your prospective client the pitfalls of tupe
ask the client how long the cleaning company have been on site
ask the client how long the operative has been there
when you ask the cleaning company for the info make sure it matches, some might not match.
the argument about gettinga poor service from the encumbant clenaing supplier is
poor management
therefore the argument, is
we can manage the contract better, and therfore the quality, if the cleaner that you inherits, doesnt perform the tasks satisfactorily then the discipline route and management of the clenare out of the position can take place.
you will need to document and record everything of that process, a letter or letter of complaint from the client will help, even copies of previous complaint letters.
regards
martin