I'm away about 50-70%. I did the opposite. It's my place, with a roommate. I chose from the ads very carefully before I found a person, well screened that understood they would get someone coming and going at odd hours, infrequently. It works. I was fortunately around enough in the beginning to get a sense of their way of life. It also helped I happened to see how they were living before they become a roommate. They pay a majority share of the rent because they use that portion of our place. I pay a much smaller amount, but give them the freedom to do as they place, provided they do sensible things (parties, but keep the place clean, quiet, don't break things). It's a careful balance. I can't stress screening the right person enough. It pays great dividend.
For my car there's not much. I use a ridesharing program to help pay the infrequent commute to work, but the prices still remain. When friends are in town they can use my car. I'm home enough that it sees driving ever week or so, although you may not be so lucky.
I do find having my own place still allows me to have the personal effects of living. I find it quite costly to continue to re-buy everything (simple things to function and live) and the cost of living can go quite a bit further down if you can do things like store Costco purchases, utilize space wisely. It's the only reason I did this design. Further, I picked a less desired location, to save on overhead. It's approximately a 50% gain in overall housing prices from more expensive neighbourhoods.
Finally, in that note, I don't think there's any plus or minus to being the owner or tennant in this case, each case being an individual position. In my place, it's certainly better to rent, but if buying and having costs covered by a renter helps, I know many that do that too.
I would hasten to guess your goal is similar to mine; keeping cost of living to an absolute minimum because you're away, while gaining the maximum benefit you need from it. In my case, having my own bed to come home to, some personal effects and consistency in life are now essential. Just 3 years ago I had the room for rent you mentioned. This brings me great peace and tranquility, something I don't want to step down from. But that's just me. Finding life hacks and ways to keep it inexpensive may mean you're getting inventive and abnormal in doing things, but that's what a life on the road is all about.