Hi & welcome.
That looks a nice car. I haven't driven a 2.5S but I've heard they need revving quite hard to get decent performance. Whereas the rest of the range are pretty torquey. So a 2.5S is rare & a bit of a marmite car.
Somewhere on here should be a 944 buyers guide which I wrote years ago, but is still relevant today, if you cannot find it then ping me a message through here & I'll send it direct.
16V engines have a timing chain between the cams as well as cam & balance belts. The chain & its tensioners should have been done when the top end rebuild was done. But the belts are done on time AND miles. This is absolute max 4 years and/or 45,000 miles. If the cam belt goes it causes massive damage & on the 16V engine it can write the engine off and decent ones are becoming rare. To do the belts is around £400 in bits if you don't do a water pump & around 6-8 hours labour, with a few specialist tools needed. Not sure on availability of water pumps, some are harder than others.
The other big job on these is clutch, everything got updated to what is known as the turbo clutch later in life, not sure if an E plate would have been. The early clutches have a rubber cush drive in the centre which breaks up. Although low miles it may have aged. A clutch on a 944 is not trivial, its a lot of labour & there are quite a few "while you're in there" bits.
In short go & have a look, get it checked out if unsure. Not sure of a 944 expert independent in Essex.
Or I'm just across the river from it if you want a second opinion. Although it's almost 10 years since I owned mine.