Thank you all for such lovely comments . They reassured me that I've made the right choice.

Would anyone be able help Janice with this one?

Hi Danny, currently looking at your photo I can see trees, Sky, and space which is nice. If you cram too much on the plot I feel it would look over developed. However having a large family you do need space indoors and converting the garage would be a good idea. Regarding the extra bedroom it's a shame to fill the space between you and your neighbour. However I do appreciate the families needs. Regarding a log cabin, I just felt a wooden form of carport with storage shed at back may be better on the eye. A softer look, less brick. I do think it's an attractive house as it is and would not waste money on render. I wasn't thinking of ceiling price.

Monocouche is better as it is tinted / through coloured so you don't ever need to paint it again + if you chip it or knock it it's the same colour underneath. It's also more flexible so less chance of cracking and coming off. Silicone render by Wetherby Building Systems is probably better than monocouche as even more flexible and water resistant. If it was me I'd pay a bit more and not have to worry about it anymore.