Noise when decelerating in E825

New to forum so sorry for repeat question. Purchased 2000 GEM E825 yesterday. Seeing some comments regarding I maybe shouldn’t have.

I have that vibration noice when letting off throttle. Vibration near my feet. I saw some comments regarding splines in differential or some sort of resilient rubber shaft bumper.

I am not a do it yourselfer so what should I do? Bring it straight into a dealer? I would appreciate some sage advice and guidance. Feeling regrets at moment but problem is now mine. Help. Thank you.