Photoshop: Quick Selection Tool

Before & After

Step 1: 

Select the quick select tool. If your tool bar is in the single column it can be found fourth tool from the top, or alternatively press w key on the keyboard.

Step 2: 

Then simply left click inside the part of the image you are trying to define. You can re-size the Quick Selection Tool cursor by pressing the left bracket key [ to make the cursor smaller or right bracket key ] to make it bigger.

Step 3: 

To start, it's best just to make a simple outline and then work in the details later.

Step 4:

 If you want to deselect a certain area, you can by pressing and holding down Alt and left clicking on the area you want to deselect. Or alternatively by clicking the Subtract from selection mode in the toolbar. But by default the Quick selection tool is in the Add to selection mode. 

    

Step 5: 

 For the areas you can see through the windows you will need to use the Subtract from selection mode.

Step 6: 

Manipulate your image as you please, in this case we're going to press Shift + Ctrl + I  to select the inverse of the selected shape, in other words deselect the area that is and select the area that isn't. Then left click on the Image, then Adjustments. 

Step 7:

Once in the Adjustment sub-menu click Hue/Saturation. Then bring the Saturation down to 0, or the toggle bar all the way to the left. 

....And finally, the final results.