Haha Would be interesting to see if a valuer would actually give you more based on the floor and having a certificate for it. Thinking about a karndean warranty transfer isn't really gonna make or break a house sale. Go for lvt and if your thinking a wood plank design I'd say make sure to have some sort of border tramlines or just a single feature strip is good.
Holly, your nearest main retailer for Karndean is Cullingford Carpets in Wincanton. They'll should have the full Karndean range for you to look at and they'll have a fitting service for peace of mind. They may well have other brands of lvt for you to look at too for comparisons. Despite some of the negative remarks you'll have read regarding Karndean in this thread, the fact remains they are one of the largest brands in the market and probably the most recognised brand when the general public thinks about lvts. My personal experiences with them are positive, having dealt with them for roughly 15 years, I've had a handful of complaints and can say that if the complaint was legit they came good for it. However, in a couple of instances they refused to help on the grounds that the floor had not been cared for properly. A lot of folk buy lvt and assume that its bullet proof, ITS NOT! Any product is susceptiple to surface scratching with use, keep your floor clean and as grit-free as possible and it should serve you well.