Noise Isolation Booths

I live in a self-contained annexe which is timber-framed and well insulated for heat but not, unfortunately, noise.

At present my way of reducing the noise levels take the form of ear plugs (mainly for use when sleeping), a pair of on-ear headphones for listening to the radio/TV,  a pair of ear defenders, and a pair over-ear noise-cancelling headphones. There are times, however, when I do not want to use any of those methods (for example because I am not keen on putting things into my ears or because of the heat and I have been looking for other ways of reducing the noise levels (alas, it is a waste of time trying to get people to be more considerate).

I have been looking at noise isolation booths. My initial searching seems to show the ready-made booths are tool tall (my ceiling height is 2.01 metres) and too costly (a few thousand pounds). Subsequently, I have been considering building a noise isolation booth.

My initial thoughts were to put my computer desk in the booth but I also thought about a booth with just enough room for me to sit and read. The former would take more room and be dearer but would be more practical.

Has anyone bought or built themselves a noise isolation booth? If so, I would really appreciate your thoughts and insights.

Or perhaps there are alternatives I have not considered.

Finally, I would like to keep this thread serious and would appreciate it not becoming a humorous thread. Thank you.