I would like to offer an alternative perspective of this problem set you are discussing.
I am a small boutique designer and manufacture having done limited sales over the years. I retired from the audio community having designed and manufactured many products now considered classics.
Having decided that the dealership network is not a viable way to do business (not the dealers but the process, I once owned an audio Rep company so I have seen both sides, and not chasing sales to make 'the nut' on a monthly basis, my goal has been to revive the fun of audio in my products and to meet new people of character in the audio community as you can see from my website at www. a
ustinaudioworks.com.
The scam issue has been a big concern - I use Paypal and direct payment with great caution. I offer a money-back guarantee which means a returned product is technically no long a new product but is used. This means that it can't in good faith be sold as new and the revenue from it has to be diminished so I take a financial risk with every sale. Over 60 years in audio has taught me that there are a lot of really crappy people out there who engage in all aspects of audio buying, selling, pontificating, influencing, and following.
My solution to this dilemma has been to not selling a product without getting to know the buyer first. Not email, but the old fashion way, one or more phone calls preferably with video. I want to see their eyes and I want them to see mine. I don't need your sale but am seeking your pleasure in your audio experience. If I think you are a flake I will not further engage. Obviously this approach is not scalable, but it is soulful. In the end we both feel good, which is a significant part of the goal.
This has worked quite well for me, if I was selling or buying used gear I would apply such an approach.
Consider that some time invested up front, and the willingness to say 'NO' to a deal are major components of keeping this fun.
Regards, Barry