Yes, HDMI over Ethernet is a viable solution for your scenario. Here's a breakdown of what to expect based on common experiences

Pros:
Cost Savings (Potentially)

As you mentioned, it's likely cheaper than renting multiple cable boxes long-term. The initial investment in the HDMI over Ethernet extenders will need to be weighed against the monthly rental fees.

Centralized Source

You can control your cable box from any of the four TVs.

Reduced Clutter

Consolidates your cable box setup to one location.

Relatively Easy Installation

Once you have the right equipment, setup is usually straightforward (though running Ethernet can be time-consuming).

Cons



Not Cheap Upfront

Good quality HDMI over Ethernet extenders, especially those that support 4K and advanced features (like IR return), can be expensive. You need a transmitter for the cable box end and a receiver for each TV.

Quality Concerns

Lower-quality or outdated extenders can introduce video quality issues (color banding, artifacts, dropped frames) or audio problems (sync issues, loss of channels).

Ethernet Infrastructure Required

You need reliable Ethernet cables running between the cable box location and each TV location. This might require running new cable through walls or ceilings, which can be difficult and potentially costly.

Bandwidth Considerations

If you plan to use the same Ethernet network for other high-bandwidth activities (streaming video, gaming), ensure your network infrastructure (especially the switch) can handle the additional load. Dedicated Ethernet lines are generally recommended for the best performance.

Remote Control Limitation

You'll need a way to control the cable box from each TV location. Many HDMI over Ethernet extenders include an IR (infrared) return feature. This allows you to point your cable box remote at a receiver near the TV, which then transmits the signal back to the cable box over the Ethernet connection. If the extender doesn't include IR, you won't be able to change channels or control the box from the remote locations. Some extenders also offer CEC (Consumer Electronics Control) passthrough, but reliability can vary.

Compatibility

Ensure your cable box and TVs are compatible with the HDMI version supported by the extenders (e.g., HDMI 2.0 for 4K@60Hz). Also consider HDCP compliance.

Things to Consider Before You Buy



HDMI Version & Resolution Support

What resolution do you want to support? Is it just 1080p, or are you looking for 4K? Make sure the extender supports the HDMI version and resolutions you need (e.g., HDMI 2.0 or 2.1 for 4K@60Hz or 4K@120Hz, respectively).

Distance

What's the distance between the cable box and the farthest TV? Ensure the extender's advertised range is sufficient. Keep in mind that advertised ranges are often under ideal conditions, so it's better to have some extra headroom.

IR Return

Absolutely essential for controlling the cable box from each TV location. Verify that the IR return system is reliable in reviews.

HDCP Support

HDCP (High-bandwidth Digital Content Protection) is a copy protection scheme. If your cable box transmits HDCP-protected content, the extender must support HDCP.

Ethernet Cable Type

Use Cat5e or Cat6 Ethernet cable for the best performance. Cat6 is recommended for longer distances and 4K content.

Network Switch (if needed)

If you're running all the Ethernet cables back to a central point and need to split the signal, you'll need a network switch. Choose a Gigabit switch for adequate bandwidth. Unmanaged switches are fine for this purpose.

Reviews

Read reviews from other users. Pay attention to comments about picture quality, reliability, and IR return performance.

Common Extender Brands (not exhaustive)



OREI

Generally considered a good value for the price.

AV Access

A wider range of products with varying prices and features.

J-Tech Digital

Another popular brand with a good selection of extenders.

Gefen

A higher-end brand often used in professional installations. (More expensive).

Atlona

Another brand considered a step up from some of the cheaper options. (More expensive).

Alternatives



Wireless HDMI Extenders

An alternative to Ethernet if running cables is a major challenge. However, wireless extenders can be prone to interference and may not be as reliable as wired solutions. Quality can also vary greatly, so research is essential.

Streaming Services

If the content you're primarily watching is available through streaming services, using separate streaming devices (Roku, Apple TV, etc.) at each TV might be a more cost-effective and flexible solution.

Cable Box with Multiple Outputs

Some cable boxes have multiple HDMI outputs, but this is rare and often doesn't allow for independent channel selection on each TV.

Before You Buy, Test!

Before you commit to running cable everywhere, buy one extender kit, connect it between your cable box and one* TV, and thoroughly test it. Make sure the picture quality is acceptable, the IR return works reliably, and there are no compatibility issues. This will save you a lot of potential headaches.

In conclusion:

HDMI over Ethernet can be a good solution, but it requires careful planning and choosing the right equipment. Don't go for the cheapest options – invest in a reputable brand with good reviews to ensure reliable performance. Weigh the upfront cost against the long-term cost of renting multiple cable boxes, and consider whether alternative solutions might be a better fit for your needs. Flag for review