They are good units, but nowhere near the helix series. The 997 can only be linked with another unit via a interlink box, they share limited data, and I'm not sure about linking with anything other than a 700-1100 series. Basically just waypoints and tracks. I bought two recently. I paid $400 for one and $425 for the other and both were complete with transducer, gps puck, mount, and power cables. I think the transducer itself new is $150-200. So even for a low hour unit I probably wouldn't pay over $300 if it needs a transducer. The power cable can't be but $20-30 I would think, and gps puck is about $100-120 new.
2003 Ranger 521VX 35th Anniversary 250 Yamaha
1979 Ranger 168V 140 Evinrude - Papa Smurf