You need to check for rising damp and especially for rot etc. to floorboards. Unless your engineer can get permission to lift carpets and some boards you really won’t know what’s down there. Check the damp proof course, especially in the extension and the floor in this area for damp. Check for damp at the back of the living room. Look for bubbling on plaster – a sign of damp. Don’t assume that your engineer will take care of everything. Put your requirements to him / her in writing. I agree with Fingalian to check out the tank in the attic. If it’s cast iron you will have to replace it. Check the water pipe to the rising main. If it is lead you should replace it. All lead pipes will need to be replaced. Check that all plumbing is to today’s standards. Check the wiring to ensure it is up to scratch and not a botched DIY job. Look for cracks running away from the house outside as this could be a sign of subsidence and any cracks in brickwork, especially cracks that run through bricks, window sills, etc. Pull back any heavy wardrobes etc. in back bedrooms and check for cracks. Lift up all loose carpets to see what the owner is hiding. Pull back furniture downstairs in corners and check for damp. Tap the plaster, wallpaper, especially incorners, to see if it has bubbled or sounds flaky, hollow, i.e. for signs of damp or water penetration. Check that the ridge tiles on the roof are straight, sagging here could indicate poor roof support, also the chimney should be well pointed, i.e. not likely to fall down. Check if the attic is insulated. Even if the woodwork looks in good condition check for woodworm, etc. Kick the skirting boards and see if they are rotten, have woodworm, etc. Check soffits, weatherboards, etc. as these may need replacing. Then ask the engineer for a list of renovations that are (a) essential (b) optional - with estimated costs, if possible. Don’t be scared to put ‘real’ modern furniture in a 1930s house. Real modern furniture, i.e. furniture designed in the 20s and 30s, art deco, Bauhaus, Eileen Grey, Corbusier, etc., if it is to your taste, will look fine.