Dont be intimidated!! I think he's trying it on. He cannot tell if there is asbestos in the ceiling artex without a lab report. Unless your wiring is visibly poor, a surveyor will not be able to tell if it needs replacing (his survey report probably covers his back by saying that the electrics have not been tested). Lastly, if the partition in your attic is adjoining another house, I would be surprised if it was only timber in construction. I dont know the size of your house, but �4500 sounds like a lot of money to chop off for these apparant defects. Either hold off for another offer or seek advice from your own surveyor or friendly architect (like me!)