TL;DR - airplane ownership is great, just be prepared for how involved you need to be in maintenance (a lot). When you rent them, you are paying for that to be someone else's problem. When it is yours, you are in charge of keeping the thing airworthy. Make friends with the A&Ps, buy them drinks whenever you see them. They have a tough job they aren't paid well enough for.
After a few more days to think on this - the availability is most of the reason to own an airplane. It is basically always available, even having partners in it. They either are or will be friends of yours, so worst case you end up flying with them when you all want to use it. This also works out better if at least one of you is a CFI. A&P even better. Scheduling conflicts with 3 or 4 owners, assuming you all have day jobs, basically doesn't happen. The costs are also reasonable - still well cheaper than renting a similar airplane.
The availability is not so great for maintenance - you only have one airplane. Even doing everything you can yourself in Part 43 Appendix A, you will end up waiting for some $50 part to show up that ends up taking weeks. This has been really bad since Covid. Me as an example - my airplane has been down for 3 weeks, for an annual that probably took less than 2 days to do. Waiting on one part. That costs almost nothing. That needs to be there to conform to the type certificate, but has almost nothing to do with airworthiness. This happens a lot. Source your own parts when you need to, no shop will look as hard to find something as you will. And join the type club for whatever aircraft it is. You'll have more luck finding stuff there, or at least the direction towards the paperwork for using something else.
There is a pretty serious shortage of GA A&Ps right now. Easy stuff, like changing a tire or a battery gets scheduled a week out where I am (we do try to do that stuff ourselves usually). You need to schedule annuals a year or so in advance. Seriously, you really do need to be able to do most or all of the owner allowed stuff on your own. And do some good diagnostics on things when they are broken. Telling the shop "the brakes are soft?" They might not be able to find the problem. Telling them "I found a pinhole leak in the line behind the carry through spar under the floorboard?" It will probably be fixed in an hour. Expect lots of stuff like that.