Looking at a couple of the 125's for my daughter.  TTR, DRZ, KLX, for some reason the DRZ's are way cheaper than the other two brands.

Anything to watch out for on these bikes?  I assume they are as bulletproof as the TTR's, CRF's, KLX's?  Mods seem to be about the same as well.

Guy has an 07 he says in great shape, have not seen pics or the bike yet, waiting on pics so far.  He will take 800.  Just wondering which direction I should go

Very reliable bikes. I had one when I was younger and as long as you change the oil and keep the filter clean the bike is bulletproof. Great transition bike for the kids, the only mods I did to mine was an fmf silencer and a uni filter. I still have the 07 sitting in my garage and all I know is I wouldn't be selling it for 800. Seems like a great deal if it checks out.

We've had two of them, one is still bone stock, KLX125L (Suzuki manufactured with green plastics), the other was  DR-Z small wheel that we souped up every way we could. Can't complain about either of them. They like to have their valves adjusted often, but other than that, change the oil once in a while, clean the carb every now and then (or drain the bowl when you park it for more than a week).
Scored the KLX two years ago for $600 cause the PO lost the silencer guts to it and it wouldn't start in 20 degree weather in January. But it did have a title and we had a spare motor at the time, so I wasn't too concerned. Put the guts back in the muffler, cleaned the carb, adjusted the valves and off she went.

I just picked one up (DRZ 125L version, 2006) for $700 in super clean condition, hardly used, but carb was gunked up from storage.  Picked up an aftermarket carb on Ebay for $46, put it on, and it runs like a champ.  Will clean/rebuild original carb as backup when I have spare time....as in...never!  Great bike, easy to handle and reliable.  Get it.