i have had to (yea - we still have these around) capture some old tapes in several passes and play around with tracking/skew each time and conform it all back later .. Clean heads and rollers will help an awful lot also. They crud up even in non use ..

A tape may have drop outs on it also - specially if it was improperly stored..

Thanks for the input, may have to go the eBay route and play with the tracking and skew. Are there any Models that are more desirable?

Thanks again..

Lots of stuff to be aware of. Firstly there's two kinds of UMatic, high band and low band, I think the high band machines will play back both but not the other way around.
Secondly you at the VERY LEAST need time base correction.
Ideally you want a deck with RF out so you can hook it up to a full TBC and dropout compensator, these things were a card file full of cards and weigh quite a lot.
I'd try to find someone with all the right kit that knows what thy're doing, even if you've got to ship the tapes a fair way away. Just buying a bit of gear will most likely not solve your problems.
If you're sending it out to be done, ask a LOT of questions about what sort of gear they have and how much effort they'll put into getting the best possible video off the tapes. If they sound cheap, give them a miss, expect to pay good money for someone to put the required effort into the job.
As has been said above you may need to get them to do several passes. Get them to record everything and then patch it back in Vegas.
Sadly though much of the UMatic stock just wasn't up to the job, some tape formulations had serious issues with media shedding, if you've lucked out with this, I'm afraid much of your video is now just rust particles inside a plastic coffin.
Bob.