I'm a 46-year old account manager at an insurance broker with no spouse/kids, a decent amount of assets & a very low cost of living. I could very easily live (& still save) on half of my current salary, & think I would find my life much more to my liking with less hours spent at the office, so I'm here to solicit advice on selling my current employer on a reduced-hours arrangement.
The barriers to my going part-time: I have clients that would need to be taken care of when I'm not there, so I have to make the case that my assistant can take care of them in my absence (she can - she's the best assistant I've ever had), or I need to be moved to a team that has more than 1 account manager so the other one is my backup, or I need a new position that does not involve the daily client service that I now perform.
I was able to successfully negotiate a (larger than normal) raise a few years back when I had an unsolicited offer from a competing firm, so I believe they will want to keep me, & the reduction in my salary will be appealing to them, but I'm not at all sure they will be open to my working part-time. Any advice welcome & thank you in advance!
(My motivation is primarily to gain more free time for care of an elderly mom & improving my own health/fitness, but I also have philosophical/political reasons for wanting to go Galt-ish.)
Back in 2001, I had to threaten to quit in order to be able to switch from working full-time to part-time. Like you, I am single with no kids and was able to easily live on half of my pay. Like you, I needed to work at least 20 hours per week in order to retain eligibility for their group health insurance program. I did see a prorated reduction in my vacation time which was fine. I did switch from working on a straight salary to working on an hourly basis which was fine. I kept a careful log of all of my hours worked. Like you, I once got a special raise after I threatened to leave many years earlier which showed me the power of having leverage.
But the main thing I wanted was to greatly lessen my awful commute which had gotten slightly longer and lousier that year after my company relocated. At the time, my company had a telecommute program so not only I was able to work part-time but work about 2/3 of those reduced hours from home.
I had the leverage of 16 years of working full-time and the fact that I was the only person in my department who could do some important tasks so if they had a way to keep me, even at a reduced level, they needed to pursue that instead of letting me escape. This was later confirmed when another coworker who had my work expereince (she began working there the same time I did) but did not work on similarly vital projects) asked for a similar arrangement but was turned down. She had just become a first-time mother and chose to quit instead.
Other parts of my own situation are not quite similar to your own. First, I was not having to care for an elderly parent. (See more on that below.) Next, my job was not like yours in that a large part of my work included writing and maintaining programs, both of which could be done in the off-peak hours when the rest of the staff was not in the office (especially the maintenance part which was more efficiently done on evenings and weekends as to not interfere with their work). It does not seem like your job has as good a fit as mine did but is close to it.
Besides the computer programming work, I was also available during the day to handle emails, and there were many of them. Some of my other supervisory tasks were taken away from me such as writing performance evaluations (YAY!).
This telecommute deal lasted for 27 months until the company ended all open-ended telecommuting altogether. I was able to retain the part-time part but I had fulfill all of my hours at the office. I hated that because it brought back some of the horrors of commuting and I knew it would be my eventual undoing (it was). After 3 1/2 years of going to the office 3 days a week to work 20 hours, I needed some relief. So I asked to further reduce my hours from 20 per week to 12. This clipped one day per week from my commute and got me home an hour earlier on the 2 days I did work. As a sweetener, I agreed to spend about an hour a week from home checking and returning emails but would not do any actual programming work. I also had to forgo most of my remaining benefits because I was no longer working the minimum of 20 hours per week needed to maintain them. These included paid vacation time and eligilibity for group health insurance. (By this time, in 2007, my ER plan was in full swing so I knew I would be leaving soon anyway. I went on COBRA for 18 months to retain continuous health insurance.) My division's manager agreed to my request for a further weekly hours reduction. With my expenses so low, I was fine taking yet another pay cut. (My bosses must have thought I was crazy; most workers want to find ways to earn MORE money, here I was yet again asking to earn LESS money LOL!)
Then, in 2008, I had had enough of that deal, as I had to reduce my commute to zero so I ERed (the utimate pay reduction).
But back to the elderly parent issue. It still did not apply to me but a coworker I had in my part-time years was able to use the FMLA to reduce his weekly hours worked by about one day so he could tend to these tasks. I do not know what kind of benefits he had to give up by not quite working full-time, though (other than some of those I faced). I think having the FMLA in your back pocket will provide you some extra leverage to get the part-time deal you want. That is the one thing you have that I did not.
I hope you find this helpful.