If you have two different textures on those walls then I think that chair rail is called for and try to match what's in the dining room which doesn't look like anything that would be too expensive. If you are asking if you should paint that blue then I would say no but try to work that color into the room with pillows,curtains, art work etc. As you are new to the vacation rental business I will make one very strong suggestion. Get rid of the carpet! Many people would be turned off by it and dirt and stains will only give you more upkeep headaches and turn more people off. Wood laminate or vinyl planks would be much easier to maintain and shouldn't be overly expensive if you install yourself.

I too would copy what you did in dining room but I would take the wainscoting up to 48" and paint the same blue color but about 2 shades lighter. Agree with ditching the carpet. I would make the brick wall more of a feature by sanding it a bit to reveal the brick color underneath. Add a console table and some art. Might consider putting a wood armed loveseat or futon. Wood would blow up better then upholstery and futon wood provide more sleeping space. Easily replaceable cushion too. May want to put a slat divider panel on the planter divider for more privacy.

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