I got the Ferrari from my dad, so I got a good deal. A decent reasonable mileage early 348ts left-hooker is worth about £23-25k. With Full History, low mileage, immac condition they will fetch late £20k's.
Mine should sit somewhere in between, around £27k I guess.
What's it like to drive? Awesome!! The best thing is, its challenging, which means you have to concentrate 110%, which, for me, means a better drive. It gets better the faster you go - it has no power steering (and has 255/40/18's on the front) so steering is v heavy at slow speeds. gearbox is stiff, so is throttle, so its a challenge to drive smotthly - but when you do, it's very rewarding. It's all worth it when you go under a bridge at 7,000rpm with the window open (ask jv

)
Costs of running - best not to ask. I have had it since september 2004, and I have stopped counting bills at £4k.
However, that includes a service, new clucth (which was nearly £2k because release bearing and flywheel were knackered etc) loads of little trim bits, electrics, new battery, new Clifford alram etc. I have thrown cash at it to get it how I want. I'm guessing (hoping) next years running costs should be limited to an anuual service only (around £600 + VAT).
I was hoping to bring it to Newark on Sunday but I have discovered a broken windscreen over the weekend, so I may not have a windscreen in time (I want to use genuine horsey-marked glass, so if Autoglass won't use genuine stuff I'll have to source myself).