Agreed with Alk, it's one of those situations where it's best not to say anything, if that which you have to say isn't helpful in any way/shape/form.
Re: cost of unices. What I've noticed is that the best way to get a license to use a UNIX OS is actually to buy the vendor's support contract. I think the $1500/year contract is the only way to get AIX for example, and it's the best way to get SGI IRIX media. I'm sure the situation was the same for SunOS/Solaris back before they decided to do free hobbyist licensing.
Of course, in 1992/1993 when A/UX 3 was new, I'm sure that $800 wasn't really too much for A/UX, especially given it was a system on which you could do unix development and networking, as well as run standard Mac apps. Although the mac you'd run it on would cost a pretty penny (something like a Mac IIci or a Quadra 610, presumably would work fine) it would probably still cost less to get a mac and laserwriter with a/ux than to get a comparable Sun/SGI/IBM/Alpha (or whatever) box.