You can put the TV over the fireplace, not the best situation but the way the room lays out it is the only logical place to put it. If you could you should add one additional layer on your mantel that could extend it out another 4" to deflect the radiant coming from the fireplace. I would also mount it on a slimline mounting bracket and have the bottom of the TV no further than 4" above the mantle. Ideally you want the TV to be in as straight a line as possible with your eyes. You don't want to look up too high at the TV, it's like being at a sports bar. Also if you can snake up the power and the HDMI from the cable there is a box they make that has both in one so it makes for a very clean installation.

Depending on where you are with the purchase decision, get a book on home inspections, which will list all potential issues and how you can spot possible problems. Bring along a friend or family member with experience. Once you've decided to buy, get a good inspector and spring for any extras he recommends. (We were recommended to get someone to send video up the chimneys, which turned out to be unlined and not particularly safe). We bought a house in good shape, but thanks to our inspection report, negotiated down the price based on a number of items that needed to be fixed that we didn't see, but our inspector did. For stuff like the chimneys, which didn't get negotiated down, we had an estimate. Many things will be clues as to how well the house has been maintained and upgraded over the years. Have the electrics been redone? When? What about the heating? Or the roof? The house looks pristine, but you want to know if the house has been care fully and lovingly maintained over the years, or just recently painted for resale. The bath shower arrangement, for example, is strange. What happened to the shower curtain rod? Was there a miserable moldy -- or worse yet, rotting --- bathroom that got fixed up and they didn't put the curtain rod back because a quick sale was more important than doing a good job. It's great if someone else took care of headaches so you don't have to, but make sure they did a good job. Ask questions about the history of the house and its updates. Unless there's another serious buyer who sounds like he'll buy at the asking price now, honest sellers will be happy to answer questions.

based on the drawing, the wall where the bed is. HOWEVER, you mentioned that this drawing is not a true depiction of the furniture you will use and the wallpaper. if that is the case, i think the wall paper can work on either wall, it all depends on how busy this wallpaper is and how "plain" the bed is. if you go with a busy wallpaper behind the bed, you may want to keep your bed and bedding on the minimal side so that there is a good visual balance to the overall composition. if you go with snazzier bedroom furniture, then a busy wallpaper may be a bit much and you may want to put it on the other wall or use a textural option to serve as the bed's background rather then another focal point.

The blue is awesome (grey is too trendy)! The reason it stands out to you is perhaps because it's the only real colour there. Bring in the blue in a window treatment, a small appliance that sits on the counter, a pretty tray or area rug. Also, it is more appealing often if there are more than 2 colours - so right now you have a white and blue colour scheme - bring in red or orange or fushia - something from the other side of the spectrum (like you did with the yellow flowers but in a more permanent way)!