This has been a popular effect for awhile - it's one of the timeless classics of Photoshop that gets rediscovered every few years.
For the first method, which produces sort of a soft line drawing, start out by duplicating your image by clicking Image>Duplicate. This ensures that you're working on a copy & not (potentially) destroying a great original photo. (In fact, you should probably get into the habit of doing this first on all your editing chores. You could even make it a quick action with a keyboard shortcut you run every time you start a new project.) I'm starting with this photo:
Reset your foreground and background colors to Black & White by pressing
We want to use the Smart Blur filter in Edge Only mode, as indicated in the drop box at the bottom of the filter interface. This creates a Threshold-type image that is intended to be used on a duplicate layer over your original at a different blend mode and opacity setting, but we're using it by itself for the cool effect it gives.
Find the part of the image you want to concentrate on by dragging the preview window around and/or zooming in or out. When you find an area to concentrate on, adjust the Radius & Threshold sliders to get a good contrasted image, as shown:
Keep the Threshold level fairly high to get good solid lines, and keep the Radius where you get solid lines without too much jaggedness.
I was hoping for a black pencil on a white paper, though, so this needs to be changed. Create an Invert Adjustment layer by selecting it from the icon at the bottom of the layers palette:
Merge the two layers together (Layer>Merge Visible, or
You've now got a single-layer image, but you can't run filters on a "Background" layer. To make it editable, double-click the layer's name in the pallete, and press OK to accept the default name given ("Layer 0").
Open the Artistic>Cutout filter, and make any adjustments needed to get the look you want. I wound up with an image like this, using settings of 2 - 4 - 1, from top to bottom:
For an added effect, highlight your original image (the one you duplicated in the first step), hold
This creates a sort of "Architectural Digest" image effect, showing what the terrace will look like once they finish building it - cool!