You can get a mk2.5 for that budget and most issues of the 2 series are fixed in that version. I had one on a 2008 plate for a few years and it didn't let me down apart from needing a new battery. The timing belt on the 1.6 is changed every 100, 000 miles or 8 years whatever comes first. The 1.6 is the sigma engine which is a bored out version and is now known as the duratec and is similar to what was in the Ford puma. I managed to get my timing belt done for £80 from a local mechanic due to the other parts running via the auxillery belt so that was all they needed to change. You might be lucky most is done before you get it.
Oil and filter: https://www.opieoils.co.uk/f/2355/976/2008/engine-oil-filter.aspx
Pollen filter: https://www.opieoils.co.uk/f/100263/976/2008/cabin-pollen-filter.aspx
With budget brakes and tyres you should manage it. Maintenance is pretty similar to the mk1. Common problems:
Happy motoring and good luck on passing!