How to get internet into an outbuilding

Ok, so I have internet in my house, naturally. I need to get internet into my outbuilding. I'm thinking a wifi range extender mesh thing won't work because it's about 150' away and will be passing through a concrete wall, then into a steel building. I was looking on the utility pole the other day and there is a 4-port splitter (terminology?) on the pole about 30' from the building. One of the ports goes to my house. The other three lots that splitter is supposed to service are either my lots, or my neighbors property that will not be built on.
Here's my question. Is there any reason I can't take on of the three existing ports and run a coax into my outbuilding? I'd then get another modem and router and have internet in my shop, that will soon house my home office.  

Would this be stealing in any way? What am I not seeing?

Probably a wired setup like you're describing will be your best bet. I have a similar setup and have tried range extenders (didn't work), ethernet over power (even worse), and a mesh system with repeaters set up at strategic intervals. That sucks the least but it still sucks. 

Wired would be preferable. 

I cannot comment as to whether or not running a wire from a service pole station will a) work or b) be considered theft. 

You probably need something like a point to point wifi bridge. 

Something like this. 

We are using several of these with access points to throw wifi over most of 30 acres for cell coverage at some property without cell towers. They work fairly well. 

In reply to DrBoost :

Depending on your cable company they may or may not do that.  The modem won't just work without them activating it.  Some companies if renting will just charge the rental fee on the second modem.  Some will charge full internet fees.  I know one that would say they would just charge the rental fee then months later decide to charge the full fee.  Either way it's not the best way to do it.  Wired would work but I hate bridging separate electrical circuits with wire.  I'd look into optical just for that reason.

Internet into an outbuilding?

Isn't that technically outernet?

I'll be here all week.  Don't forget to tip your waitress.

In reply to Toyman! :

Super curious about your example.  How many bridges and access points did that require?  How did you power them?  etc.

In reply to nderwater :

Coverage is through 3 buildings. Fiber comes to the house and runs through a router. From there, it goes to a directional Tx/Rx that shoots it to the other two buildings. Each building has it's own router. Each router is an access point and has 1 or 2 access points plugged into it that broadcast wifi. One access point covers the area between the buildings, the others push that signal out and cover about half the property. 

Since the property has no cell coverage but does have fiber, we set it up so my 84-year-old parents would be able to call for help if they needed to. I can get the specifics from my brother if you like. I was the manual labor running the wires and mounting the hardware, he's the one that made it all play nicely together. 

Edit to say: It also means I can be sitting in my motorhome streaming TV or working on the computer over the Wi-Fi, even though I'm about 500' away from the house where the fiber comes in and a little over 200' from the nearest access point. 

I use a power line adapter to get internet into my garage and it works pretty well. But the total run distance is probably 75'. You have to be on the same circuit panel though.

I would also recommend a point to point wifi bridge.

I installed Ubiquiti "Nanobeam"  Devices at a customer place 6 years ago, works flawlessly.

You need line of sight, and ideally both devices on Poles/Mounts outside, facing each other.

150 feet is well within the 328 ft. length limit of Cat 5 or Cat 6 cable.  Amazon shows direct-burial options if you don't want to lay conduit.  How hard would trenching be? 

What data plan do you have for your cell?  With unlimited I use my cell as a hot spot anywhere.

Direct burial or dedicated directional antennas on the roofs/facing walls of both structures would be the most robust option.  Depending on the ease of digging I would just either hand-dig or get a trencher and direct burial since the one thing that will always work is a wire.  If its a decent enough building to warrant an upgraded electrical service or water connection, would be a good time to do that as well.  

I have Nanobeams set up to connect my shop to my house. It's about 150'. I stayed away from physical wires due to grounding concerns and rocks. The Nanobeams are basically just a wireless wire from a networking point of view, they're completely invisible as far as the network is concerned and they just work.

The house side is inside the house, shooting through a stucco exterior wall. The shop side used to be inside looking through a window until I installed mirrored film on the glass, then I had to move it outside.

Mine are 5 years old and aren't as fast as the rest of my network, but the current ones are apparently 450 Mbps. Even my old ones are fast enough to stream stuff to the TV in the shop and do browsing, so that's all that matters to me.