Excellent guns, in the days of metal and bluing perhaps Walther's best gun made.
Competed in the XM-9 trials that eventually led to the Beretta 92 being adopted. It (an early version) failed in those tests and I would have to look up which test it failed.
It was then introduced in 1988 to the shooting public. Walther as always has sucked at marketing and even more important has never been able to price a product in a decent price point. Thus the gun did not do well commercially and did not garner any big government contracts.
Walther added the modified and simplified P88 C (Compact version) in the early 90's in order to lower overall production costs but again it was still a pricey gun and it arrived in 1994 and thus got caught up in the 10 round mag ban, so high cap 14 round mags are even harder to find for the compact and thus way more $.
Today the cost of magazines (even 10 rounders) is very very high, if you can find them.
Some have said it was one of the finest and most accurate 9mm service pistols out of the box. To me the P88C grip was better, the P88 ambi decocker system made the standard guns grip fatter than it should have been.
$1400 is a bit high, unless mint in the box, unfired, with 2 high caps etc... but is not way way off.