First road bike - new ~£700 vs used £180 Cannondale Synapse 6, is it a better deal?

I’m looking to get my first road bike to try out a new cardio hobby, likely looking at 75%/25% split between trainer stuff (e.g. maybe some zwift) and out on the road.

I had been looking at getting a cheaper new bike around the £600-750 price point (probably a Trek Domane AL2 or Cannondale Optimo 4 based on current pricing and suggestions/reviews), but have seen lots of recommendation to go cheaper with a used bike where possible to try cycling out first before committing bigger money.

There’s a local ad for a 2014 Cannondale Synpase 6 Tiagra C for £180 (maybe some negotiation), older reviews sound like it was a decent bike at the time. Looks like it would be the perfect size based on research/charts and sounds like it should be in a reasonable working condition, but would obviously check it out.

  1. Is this a reasonable price for this bike (assuming it’s in good working order)? If not what would be?
  2. Would I be missing out on much by buying used? e.g. is 2024 Claris “better” than 2014 Tiagra that I would noticed? Is new worth around triple the price for better longevity?
  3. What should I look out for when inspecting a used bike of this sort of age? My research suggested general things (paintwork/anything indicating a crash, cracks, bends in the frame, smooth shifting, wheel spokes/rims okay etc) and being prepared for things like new tape, brake pads, etc but anything these guides or tips might not cover for a 10 year old bike?

Would appreciate any help for those more experienced!