I'd go for option 5 for upstairs as you can make the attic room into a bedroom further down the line. I wouldn't want a windowless bathroom and it'd be easier to run plumbing directly over the former bathroom. Honestly speaking, £11k is not going to cover the upstairs bathroom and kitchen unless you're very handy and are going to do most if this yourself. Even then a new kitchen will blow that budget. I would do the upstairs bathroom and use whatever you have left to rip out the old bathroom suite, lay some lino and have a WC / utility room with the hopes of a bigger renovation of the kitchen/dining/lean-to space further down the line.

Opening up some will surely help. Like Jonathan said, there are many many options. I changed the hallway, some coat space, double glass door to let in more light, loo. Then kitchen with pantry, as there are plenty full bathrooms. Backdoor for muddy/wet shoes on the side. Since it is such a large space, how about a massive sofa in the lounge? And window seat, if height allows. Keep the downstairs bedroom and bathroom, as it can be a playroom, a guestroom (b&b?) or even future master bed. I did open up the dressing area, to make it brighter. Washing machine could go anywhere, I drew them there, but it would be quite the walk with hampers, so might it be an idea to place it upstairs (eaves storage perhaps?). Upstairs I opened up the study, as the master bedroom ate the window. I tried keeping most loadbearing walls (or which seemed to be) though the chimney on the left had to go anyway. Kept the landing storage, for linen, towels, seasonal clothing, christmas decoration, there are always things that need a place. Certainly move the heater though (if it's still there). Also think about heating, insulation, efficiency. Things that will make it more comfortable and pay themselves back in the long run. Planning is key. Hope it will help with creating your future layout and dreamhouse pleasures.

That is super useful thank you. I might think about putting the washing machines into the utility room, moving the bathroom into that space then using the bathroom space as a place to take off shoes/store coats etc. It’s great to see a different perspective so I really appreciate you taking the time to do the drawing.

Thanks for your comments! The first plan has general dimensions but until we get the keys thats all we’re working with unfortunately. Yes definitely agree with you that the new extension will have space for a dining table, just wanted to mention that we personally will be using it as a lounge space 🥰 We’ve done so much research on similar properties so understand what we need in the space to get the most value partiucularly within our local market, it’s just a matter of working out the best means to achieve it. I think I forgot to mention that the house is essentially derelict so the old extension needs to come down in place of a new one and everything internally (including plumbing and electrics) need to be replaced so we have a blank canvas!! Really appreciate you sharing your thoughts!