I bought an abandoned Dufour 45 without a survey, knowing it that had been grounded and repaired. When we got round to getting it surveyed the surveyor saw the hull had delaminated. We employed a contractor to do the work. The previous repair hadn't been done properly. He kept grinding away all the bad areas. he got everything (we think). The boat is now in the water. It was a long process over 2 months. It cost us 12,000. There is still traces of white dust in the stringers that eventually gets flushed into the bilge and clog the filter. the chemical smell takes a while to get rid of. If you have got a bargain price for the boat (like we did) it's worth doing. If you search Hanuman on Facebook there are some photos of the work. Yours doesnt look as bad as ours did.
The membership association for owners of Dufour Yachts