This is a really awkward space! What about trying to build a unit into the corner which seems to be dead space. This could house the television and other bits like dvr,amp etc. The unit could then extend out towards the door in length and in height either up to the start of the window or up to the start of the blinds. I would suggest drawers for toy storage and books above. In this way you leave the windows clear for light plus it looks like you have a pull down screen so the tv would be out of the way of that. This arrangement would also hide all those wires and cables! Ikea have some good examples of storage which you could adapt or copy, such as Besta which illustrates the extended toy storage. http://www.ikea.com/gb/en/catalog/products/S39927155/

I think the first layout is fine. You might want to consider moving the door for the storage room of the master bedroom so that it opens into the hall. That way the kids can use it for overflow storage. Also, that hallway is big enough that I think it could hold a large armour, providing more closet space. (There's no need to sleep in the same room as your clothes, so long as they're not too far off.) Also, don't forget that while the drawing shows kids in double beds, this need not be the case, so there will be more room for furniture (dressers or whatever) in their rooms. Finally, that step to bedroom 4 will not be odd at all. I've seen it in other homes. It looks clumsy in the drawing but it isn't. What you'll see when you come up the stairs is a bedroom door on a slight diagonal. It's only an odd jagged step if you walk like a robot, in straight lines along the wall, which is what your eye is doing on the drawing but you won't do in real life.

There is nothing worse than ceiling-mounted lights--harsh shadows, flat lighting. They are strictly for utility. I would put a large-ish, shallow cylindrical shade on them and put nothing more than a 15-watt bulb in them. Use them strictly for lighting your way as you walk through the room. I agree with Vincent; the chair in the corner doesn't fit at all, nor does the one under the A/C unit (put that one with its mate behind the love seat). And the curtains look smooshed. I think the problem with the bookcases is that they are uninteresting. Did you buy books-by-the-yard? What are all those identical books? They are visually uninteresting. I'd get rid of some of them and get some colorful ceramics/glass/photos. The room is absolutely overwhelmed with furniture. It needs one less love seat. Do you really need all of them? Pushing them against the walls/curtains so tightly just visually emphasizes the fact that there is too much furniture. I don't think a mirror above the fireplace will work. When people are sitting down (which is most of the time), all they will see is a reflection of the ceiling--the plain, white ceiling. Get some real art in there with some color.

Low ceilings = flush lights. Before you purchase carpet get 5 or 6 agents round to value. Ask each for their opinion on what they think will appeal best. Ask them if you could get away with just laying underlay. For the wow factor make sure your budget is spent on items that you can take with you - think a huge 6fx3ft mirror, a bright modern art print, a mirrored console table etc. No need to splash out much just one item in a room or two to indicate wow. A patio table and chairs in the garden are also needed for the selling photos as they will help the buyer to see scale and the garden will appear more homely. A bowl of fruit in a chrome wire bowl in the kitchen will also add wow - stage with green apples and yellow lemons for example. So, to sum up the spend on 'wow' should be limited and only to what you take with you. As for the estate agents some of them do try very hard to give good sales advice so when you book them to value explain that the property is being flipped and you would welcome any ideas on how to present it. You may be surprised at what they suggest.