Here is a little description of that boat from Eddy Flower:
Pyranha Creek 280
It is an old-school design. It would probably be OK for a first boat, to learn how to roll and run some whitewater. With a boat that old my first concern would be UV damage. Try to find out what year they bought it new. If they left it out in the sun at all then it is probably brittle and will explode on impact.
I probably wouldn't pay more than a token amount ($50?) for it. You can hardly give away old-school boats these days. Obsolete designs are not really worth anything but they are good for instruction and for picking up the sport.
Whatever you do, don't pay much for it. If it is an acquaintance who owns the boat they should give it to you. I don't think it is very reasonable to ask for money for a 15 year old kayak design. It is kind of like trying to sell a pair of skis from 1994.
Here is a snippet of some advice about the different kinds of boats that I gave to a friend who was getting into the sport:
"There are several categories of whitewater kayaks. The categories are changing a little bit with advances in design and in the general knowledge of the boating community but the basic types are: 1) playboat, 2) river runner, 3) creek boat
A playboat is like a high performance sports car that is very unforgiving, low volume, for doing freestyle tricks, and is unsafe on the river in the hands of a novice. (about 50 gallons of volume?)
A river runner is what a novice wants. It is in between a playboat and a creek boat in terms of volume. The edges are softer than a playboat so they don't grab the current as aggressively. They are easy to roll. (about 50 to 60 gallons of volume?)
A creek boat is specifically designed for quick moves in violent whitewater, for not sinking too deep and for surfacing predictably after big drops. They are built with extra plastic so they are heavy, and they usually are high volume (60 to 80 gallons of volume?)
There are two basic hull shapes: a planing hull and a displacement hull. A planing hull is flat like a table on the bottom with hard chines (sharp transition from the bottom to the sides). A displacement hull is like a bulbous rounded shape that presents a fairly constant cross-section to the water as the boat is tilted. A modified displacement hull would be a displacement hull with a "kind of flat but still pretty round" bottom and a very noticable transition from the bottom from the sides.
The displacement hull has low primary stability and high secondary stability. The planing hull has high primary stability and low secondary stability. Primary stability is what keeps you from tilting your boat up on edge on the side. Secondary stability is what keeps you from going from tilted up on edge to upside down.
A river runner will probably have either a planing hull or something in between the two. You most often see a full on displacement hull in a creeker design for steep low volume creeks.
There are so many boats out there it is hard to pick one but if you stick with "I want a river runner with a design that isn't ancient" then that might be a good start. The ancient boats are not that bad...I just don't like paddling with old technology when so many advances have been made. I would say try to stay with a boat that was not designed more than 5 to 10 years ago, preferably within the past 5."