Avoid the 1 litre Corsa, it's beyond crap. The 1.2 is OK, I had no problems with mine, but again it was pretty slow in my 2004 Corsa C. I drove a 1.2 Corsa D when my Vectra was in getting ruined, and it was OK for round the town, but a dead loss on the motorway. The 1.0 and 1.2 are both timing chain, but the tensioners are rubbish in them so actually that's a downside on those engines.

The 1.25 engine in the Fiesta is a wee gem, a Yamaha designed engine. They're revvy, and pretty economical, and I personally think they're better than the 1.4 Fiesta. The 1.25 is 100k timing belt from memory.

In defence of the 1.0 litre Corsa engine, I would mention that it is identical to the 1.2, apart from a different stroke and bore, and one less cylinder. So lighter.

Neither is noteworthy for performance, reliability, or economy.

Most Corsas fail due to poor maintenance, with a small sump holding 3 litres, poor ownership and extended service intervals, a fully stamped history won't tell you much.

A Corsa with more frequent oil changes than those recommended is likely to be in better shape.

They fail with high oil consumption due to failed rings at any mileage and there is no easy way to tell with a casual test drive. But any start up rattle or blue smoke, walk away.