Builders Warehouse is a ****!!!!

I purchased a Ryobi brush cutter at builders on the 22nd December 2023 for personal use, upon using the machine I picked up that it was faulty as it was releasing dark smoke and it vibrating to a point that the engine turns. I returned the machine as it was still under warranty, I was then told of Ts&Cs that were not on my purchase receipt nor communicated to me during the purchase time. As part of the conditions, they say they will take the machine to their assessor then if it is rejected I will have to pay for the assessment fee and repair fee. That is ****ming because their reasoning is that I overworked the machine of which I didn’t! I didn’t even complete a quarter of my yard!