I can't really agree with much of that.
Yes it's been damaged, but it will have been repaired with new parts therefore it could be deemed a safer bet than a high miler with worn out parts.
Yes it will be harder to shift on resale, but buy cheap and sell cheap. CAT D's are usually about 25% less than normal. Therefore, most 04 cars are around £8k, so anything less than £6k for this would be a good price imo.