I do almost everything at home. My system isn’t bad (and I have a backup headphone system): http://cgi.audioasylum.com/systems/3367.html Also a brief description about my room treatments: https://www.audioasylum.com/messages/hirez/224992/howdy-an-update
My wife and daughter have great ears (and enjoy music) which is nice for making sure I’m not overlooking anything.
Then I send the code off to PS Audio where they listen and give me their impressions. Paul and I listen for different things and that’s a good thing: we cover a broader range of customer preferences. I don’t think we’ve had a case where there was something they heard that I can’t reproduce or that I disagreed with. We don’t fight over things like frequency balance, sound staging (where our two systems differ greatly), or a lot of other things that people might tweak. At times, they do say things like “the bass seems a little sloppy” and I can usually find some technical thing to address address their issues. Paul is always pushing for things like “lower noise floor”, “more bass extension”, and I’m happy to try to find something that I can make objectively better that ameliorates those concerns as well as the concerns expressed here on the boards. Also I like to think that if I didn’t like their choice of which one out of the twenty that we could either get some more versions to choose from or that I could make a change that addresses the perceived weakness of a set of twenty. It hasn’t been a problem so far.