You should like your competitors content on Facebook, with your personal account, not your business Page of course.
Why would you want to do this?
It is the simplest way to keep track of what your competitors are putting out via their Facebook pages and it is completely free. Some organizations create a “fake” account with a single sign on for anyone to use. Quite often this account is used for managing their own social media, but also for checking in on their competitors.
There are also platforms out there that allow you to monitor your competitors content. www.brand24.com is a great one that I’ve used in the past. But on a “no budget” policy many small businesses need to be creative. So simply liking their content on an account of yours, unrelated to your business will provide you with quick access to all of your competitors content.
One of the biggest reasons why you should like their pages and frequently like their content is because at that point your account will become considerably “low hanging fruit” in terms of paid content promotions on Facebook. Often a paid campaign will be segmented out, and one of those campaigns will be targeting “people who interact or engage with our facebook page”. That is an optimal way to see just what your competitors are spending money on promoting.