It will not be the sport but the Ambient trim
http://www.buyacar.co.uk/skoda_octavia_ ... _157.jhtml
The 1.9 105 bhp is good for around 50 mpg I have one, long runs have seen nearer 70 if you keep to the limit
take it for a long drive and once warmed up stop with the engine idling, and listen for a sound that sounds like a cement mixer full of gravel that will be the duel mass flywheel on the way out, if all is quiet it will be OK but should it go you can get a normal flywheel and clutch in its place for half the cost
find somewhere you can drive the car in a circle in both directions listen for a clicking sound if there is one its the CV joint
Make sure the belt tensioner and also make sure the water-pump is changed to a metal one
Apart from that it should be OK for at least 300,000 miles if you look after it, by changing and useing the correct oil every 10,000 miles
Try to get at least 6 months unlimited warranty for piece of mind, and don't use main dealers if you can help it for servicing, unless they do the taxi service for £100
If you want the sport they come in 2.0 tdi only now and will cost around 8k for a good one but the turbos are the main worry with them