To answer the question of whether there is an aging in place design that can be purchased, requested, or emulated, the short answer is "no." This is with very good reason. Each case is different. Aging in place solutions are client-centric, meaning that they are designed specifically for the needs - great or small, low budget or higher amount - of the client and their interior living space.
Yes, there are best practices, and there are significant guidelines like visitability and universal design that give general direction for improvements, but no one should expect to find a "canned" approach to an aging in place solution that can be located online, in a catalog, at a showroom, or ordered over the phone. It just isn't there.
Aging in place, by definition, means that people get to remain in their homes - with or without any improvements that might be needed or completed. Until we meet with a client and evaluate the physical layout and condition of their home and pair that with their physical requirements and needs, we can't design or suggest any improvements. Since everything is done to fulfill the individual needs of the client, there cannot be any standard solutions for an aging in place design.
There may be many similarities among various designs and solutions that are created, but they care done to help and meet the needs of the client rather than being used because they are specified for a particular type or age of dwelling. There also is the matter of budget. Some people have very limited financial means and can only have a few things completed. Others have more substantial budgets and want more items completed. With higher budgets often come more expensive brands and fixtures also.
While it might seem that there could or should be a standard approach or set of solutions for a person wanting to age in place, there really can't be - no more than a visit to the dentist with a toothache means that the same approach to treatment would be employed each time. Obviously, the dentist would have to determine the reason for the discomfort and design a course of action based on that, the patient's medical history and general physical condition, their general dental hygiene, and the seriousness or urgency of the condition.
Some people are going to need a limited amount of help to improve their homes because their homes don't require much work or they have no conditions which suggest specific improvements. Other than adding some visitable or universal design changes to enhance the home in general terms, not that much would be indicated.
Others are going to require various amounts of work as determined by their physical needs (mobility, sensory, and cognitive), the age and general condition of their home, their budget, their priorities, and their timing. It's up to us (our team) to evaluate the living space and the needs of the client to design a course of action and scope of services - for each individual renovation.
While there are dozens of possible aging in place solutions we can create to address the needs of people and the homes, there is not a standard, one-size-fits-all approach.