Where does it say in the Robot Handbook that the Standard Low Berth is a Robot. There is mention of the definition of a standard medical chamber dimensions and standard space craft mounting that apply to common low berths and autodocs. It says this standard corresponds to a Size 7 robot, 2 vehicle spaces or 0.5 DTons.
This may be shocking, but everything built with the robot rules is technically a robot.

These have robotic slots, robot brains, use bandwidth, and are, under the rules, technically robots.
In a different thread about ship’s avatars, I talk about how Geir revealed that even the avatar controllers and receivers are technically robots (no locomotion, but brains and bandwidth).
Is that overbroad? Perhaps they should just be computerized, but that’s not how this system treats computers. Still, maybe thinking of them that way would be easier. Personally, I just consider them “equipment” built using the Robot Handbook rules.
And as it is a thread about advanced low berths it is perfectly valid to discuss the economic viability of them.
I’m not disputing that. I even agree with your assessments.
If you choose to define imperial years as 13 months IYTU that is your prerogative, but in doing so you risk fundamentally changing one of the basic economic drivers in the game (technically the Imperial calendar doesn't have months or weeks, it has years and days only). The rules talk about "Maintenance periods" rather than months and the standard calculation is that there are 12 maintenance periods per year (Core Rulebook p154). Mortgages are paid off over 40 years so if you are going to say each of those years is 13 maintenance periods rather than 12 then you might pay less per month, but you are making more payments, the amount stays the same. You also compress the timeframe for making the standard 2 jumps per maintenance period more challenging if you chop off three days per period.
I forget where I read that Charted Space uses 13 months of 28 days and one Holiday. Even so, I can repost the chart with 12 months. It won’t change things much.
I'll leave you with one more consideration. Assuming you are fitting low berths because you want to use them for commercial passenger freight (rather than for frozen watch or equivalent scenarios) you also need to consider the pay-back period. The standard KCr50 low berth pays for itself after 46 maintenance periods (with the standard 2 jumps per maintenance period), ditto the standard "advanced" low berth (i.e. the TL12+ version). The Advanced Plus Economy version at KCr68 takes 67 maintenance periods, almost 50% longer before you even start to turn a profit*.
I’ll add that to the spreadsheet for both discounted and not discounted as it does make things clearer.
*I will caveat the above as there is a common misconception regarding profitability and mortgages. Many player seem to think that if you don't make more than the mortgage, maintenance and crew fees (i.e. positive cashflow) you are not profitable. Maintenance is pretty much dead money, but crew fees are of course going to the crew, so there is a profit there if you are a crewmember and simply paying the mortgage is an investment as every maintenance period you own a little more of the ship (and ships are a collection of components so the same logic applies there as well). Where lack of positive cashflow might kill you is going bankrupt before you can realise that investment and the bank foreclosing on you, but that is a different issue.
After you have paid the KCr100 that the bank requires you to ultimately pay for that KCr50 low berth you have a KCr50 low berth you can sell on (and maybe get KCr40 for it). This will be in addition to any revenue it might have generated over its time in use so the economic viability calculation is a little more complex in the longer term.
I hear you. You do have intangible costs too. Like the number of dead bodies you have to deal with when using the basic low berth vs the advanced economy. I’ll wager most merchants would see that as a benefit worth the marginal cost increase, particularly since the berths in the Robot Handbook do use those discounts as part of the process.
Standard designs can and do get a discount as per the book. That was used by the author to match the price of the basic model to High Guard, so it is part of the system. If you chose to not use that, then the price of the one in High Guard need to be bumped up to match the basic without a discount as they are in fact the same unit. The comparisons need to be apples to apples.