My first disco

I am going to be looking for a s/h disco within the next few months. I think i've got a budget of about £1600 (but could maybe stretch to a little more!) I am after a 2.5 TDI. Could anyone advise as to:
1) What year I should be looking at for this price?
2)What mileage is acceptable/reasonable?
3)What is the difference between a 200tdi and a 300tdi?
4)What should i be looking for when i go to view/test drive them? (eg. i've heard the 2nd/4th syncro has often gone, how do i tell and is this a major prob?)
5) and finally where is the best place to look - private? trade? auctions?ebay!?
I live in Hertfordshire if anyone knows of somewhere nearby to have a look.
Thanks in advance, any help will be greatly appreciated.
Simon

My advice is read as much as you can from this forum..

Forget about the mileage, look for one with a service history; check the chassis, rear floor, & bulkhead for rust/wear; always take it for a test drive; look at the ground where it is usually parked (for excessive oil leaks) don't buy from a dealer as you'll pay a 20+% plus markup on value and NEVER be tempted to buy one that's only been owned for a couple of months - usually there's a good (bad) reason why the car is for sale.

Most importantly, have the budget and patience to fix things when they go wrong

If 1600 is the max u can afford, then lower your budget to £1400, to allow for a few niggles at the start.