I’m thinking about buying a Mk4 Titanium X Petrol turbo.

Is there a buying guide on here or elsewhere that’s worth looking at?

What are the common issues with this car?

I know the original timing belt tensioners are weak. I assume there’s an SKF or INA upgrade on the market that solves the issue. And many cars that survived to this point will probably have had the tensioner changed by now. 

Also, that the bore liners are prone to cracking. Is this a common fault? Where do they tend to crack? At the top? Is there a fix that can be applied to prevent this? Such as cylinder support or epoxy or something similar?

Any advice appreciated.

If the Focus ST225 is anything to go by, it’ll be brilliant, if a little thirsty, yes the liners can crack, but usually when pushing over 300bhp, stage one will Be fine, otherwise a block mod is necessary, which entails shims placed between the liners, so head off job, lots of filter and oil changes are the secret to a good car, obviously it won’t handle quite as good as a focus, but it won’t be far off.