questions concerning used atc 50 passive purchase


I have always wanted a pair of atc's if the reviews of them are accurate (most detailed midrange etc etc.).  living in rural Appalachia i have no real opportunity to hear them in trial...however a used pair just came up for sale...

they are passive atc scm50sl.  owner says 20 yrs old, with old-style tweeters.  they would come with a threshold amp.  
I have a couple of questions for those with experience...
1.  What should i be wary of with regard to capacitors and tweeters ferrofluid drying?  
2. is it a given that i should send them in for work? (and if so how should that affect what i offer i.e. what could a ballpark updating look like price-wise?  Or could they have a few years left in them (anecdotal experience counts)? what would be a fair price in your mind for said purchase, assuming speakers in great shape other than age?  They come with stands and grills. 
I would prefer active but have always coveted that amp.  and i am not sure how often used actives come up in price range, may purchase actives several years down road.
I apologize if topic has been covered.. i did some reading on site with other threads on the tweeter issue but there seemed no consensus.  The gentleman selling did not describe any need for these actions.  Apologies as well for poor grammar and spelling.  
thank you in advance.
fatherbrawner
You can call lone mountain audio, the us distributer. They have always been informative and helpful. I purchased used ATC 50 active towers from my audio acoustics vendor (Acoustic Frontiers) and bought a used ATC center C6CA directly from loan mountain ( also through my vendor). I had a really hard time finding a place to audition the ATCs but finally found a local store that was able to source one from ATC that was at an audio show. I didn’t want to put down the big bucks for this without ever hearing them. Actually, I take that back. While vacationing in London I went to a local hifi shop that carried atc. It was a passive version of one of the lower models. It was fine but I wasn’t blown away by them. I waited til I finally got to hear the model I wanted to buy.
Thanks much.  I'm just getting into the hobby.  What would you consider a reasonable deal? If you dont mind me asking?
Thanks lx.  i called lone mountain.  They were helpful.  Sent me to musicdirect but it was too late today. The new models are currently out of my price range.  But in a few yrs... When some things are paid off.  Would passives give me a good sense of what to expect down the road?