I'm a JBL guy.
I wouldn't pay a "friend" more than $700. As a seller I would be looking for about $1,000. I could probably get more parting the kit out.
To the guy that commented about the center looking wimpy, it's because those towers are big. The EC35 is a better center channel than 90% of what is out there, it's a true 3-way center with dual 5.25" woofers in a big enclosure. It is the best speaker in that picture and is a standout from the lineup.
These are much nicer units than the Venue series, which is quite evident if you look at the cab construction and weights compared the Venue series. Modern equivalent is probably the ES series, that has just added that gimmicky (imho) uhf driver. I don't consider them top of the line speakers but they are nonetheless built as well as the higher end offerings you will find at mainstream stores nowadays. Unless some of them were in direct sunlight, they will have many years of service left in them (except the subs see below).
As others have said, the weak link here are the subs, which although they will play fairly loud, are not particularly clean subs and they will be outperformed by even very humble modern units like the $150 BIC F12's. Unfortunately the amplifiers in these subs are not terribly reliable, either. Check for a chirp at power-up and if the auto-on circuit still works. Trouble with either is a warning sign.
If you buy this kit there are also other units from the same line that could be swapped in or used to grow into more channels. E10's are tiny wall mount sats that can work for height or surround back, E50's are a rather large "bookshelf" that just happens to be a very excellent speaker, it is just one of those designs that "works".
All in all, this is a very serviceable speaker kit with lots of life left in it. Just skip or flip the subs.