It had probably been badly neglected for many years.
It may be anecdotal but the twins I see kicking around in private ownership generally seem to be maintained to a lower standard than the IFR capable singles I see around in private ownership.
It may be due to the higher ownership cost of a twin, or due to always having a spare engine and a lot of electrical and other systems redundancy.
But if you take one in for an Annual, then unless the company doing the work is happy to collude with you on doing a "box ticking" job (and many are, especially those doing the RF/FTO fleets) you are going to get a big hit because they will want to fix all the stuff that is broken.