When everyone thought Hitlary would become the President, they dumped an irrational volume of money in to AR's and AR lowers. Every manufacturer that could make them went in to overtime and built a zillion and everyone bought as many as they could justify. And this happened AFTER a spate of awful and high profile mass shootings where many clamored for more "gun control on evil assault rifles." All this means that the pool of AR's in the nation grew at a ridiculous rate.

The market is FLOODED in a way that we have never seen and the "value" and resale of used AR's is basically pathetic.

There has literally never been a worse time to attempt to sell a used AR if your goal is getting "top value."

In your situation, you have two choices I think: keep it or get used to the idea that you will get chump change compared to what you spent on it.