I think it is a bit awkward for such a large room. As mentioned, you could fit 2 single beds comfortably, but probably under the windows, end to end. A double would fit but only realistically if one side is pushed against the wall, which is a significant compromise. I think you should definately not have the built-in cupboard, as it restricts your options. Are the dimensions fixed, e.g. are you building above something else? The radiator would be best behind the door as this is dead wall space anyway.

Good morning, It may be worth measuring the room and uploading a plan, so that Houzz designers can properly assess the room and provide an accurate layout for you. Get some measurements of walls, windows and doors, as well as the ceiling height.

I think if the location works for you and you can afford to extend, and can’t find a better alternative then it make sense to extend. Especially if you’re going to stay for a while! We are nearing the end of quite a big extension/refurb and it has cost a lot, but is cheaper than moving would have been, and we are aiming to stay here for the foreseeable future, so it felt worthwhile spending the money. If you’re extending, moving walls, new bathrooms and kitchens, it will rapidly add up, as you’ll also need new Flooring, extra windows etc Is there enough head height in the loft to do a partial loft conversion perhaps?

You are welcome! Happy to help! You can see in the drawing an example of what might be suitable for you. There are plenty of different dimensions of toilets and sinks. If we follow the standards, in a 0.9mx0.9m space, the toilet should be placed on the diagonal of the room and the sink in the corner, you can see that in the photo. Hope this helps!