I can see potential for a 3-bed by turning the downstairs reception room into a bedroom but I don’t think you’d fit a third bedroom upstairs. You could consider turning the downstairs shower room, or part of it, into a utility / laundry space. Changing to 2 separate flats could be problematic in terms of access to the first floor one - presume you’d need a shared entrance which would make accessing the ground floor front reception room more difficult. Also, I don’t know if you’d need any special permissions, plus extra fire / safety regs to turn a house into 2 flats. It seems to be potentially a lot more hassle to take that option.

Hi Emma, I think your idea is do-able but I'd advise against doing anything to the front reception room so that it's easily returned to that when you're ready to move on. You could get a slim bathroom next to it though the plumbing needed could be fiddly and therefore pricey and you'll end up with a small bedroom. The negative impact of doing this would be offset somewhat by opening out the whole bathroom area to make a sitting room with big windows to the garden. I'd square off that end wall, demolishing the old privy space where the loo is. It might be tempting to keep it as a shed, accessible from the garden, but it takes up a lot of the back wall. Gaining even that small amount of extra garden would be a plus. The existing back door could stay or, if it felt odd to be coming and going through the sitting room, moved to just inside the diner. If you were to replace the wall between the new sitting room and the kitchen/diner with glass double doors you'd bring light further into the flat and they could stand open most of the time and be closed when you wanted a cosier space. It would be ideal if you're able to keep the bedroom as a double but if that really isn't possible, perhaps you'll need the courage of your convictions and, by ensuring the new sitting room and bathroom spaces look amazing, embrace the front room as the main bedroom. Good luck and please keep us posted! Rosy RR

If the second bed doesn't need to be so big, swap the bathroom with the box room. You'd need to lose the utility but would keep a nice big kitchen. If the budget allows, you could widen that room to line up with the living room wall. That'd mean a new kitchen which may be a stretch too far but the symmetry might be pleasing!

No idea how easy it would be to move the kitchen to the rear bedroom, as both previous comments have indicated, but having the living/dining space next to the garden makes sense. The compromise is trying to squeeze in living/kitchen/dining into a relatively small space without extending into your side return. I really think you should explore the cost of an extension into your side return as it would make a big difference. If I’m correct, I noticed in Jonathan’s plan that the bathroom has been extended into the space where the back door was but if you kept its original size and simply moved it ‘down’ this would give you a little more living space.