I changed the Honda CRV I'd had from new for twenty years in March, for a two year-old Honda Jazz Crosstar. The CRV had a spare wheel on the back and I've had to change a wheel due to puncture on three occasions in that time. The last was a year ago, when I was 100 yards from home. At 84, I didn't find it a problem. The job was done and dusted in less than fifteen minutes and I was home, probably at least an hour before the RAC would have arrived. A lot of modern cars don't come with a spare wheel, there isn't any space in the boot for one. The penny-pinching manufacturers give you a can of "gunk" and a Micky Mouse air pump to put it in. When I bought the Jazz I checked it out in its compartment in the boot, at least it hadn't been used. I visit a Honda Jazz message board and the problem of, "no spare wheel," comes up regularly and many owners buy one. What convinced me was the post by one owner who said he'd had a puncture and used the gunk which just oozed out of the hole in the tyre. He called the AA and all they could do was whistle up a transporter to collect the car. It took hours. Even if you manage to get the gunk to work. The tyre is effectively ruined, as most tyre places say they can't be repaired once it's had the gunk in it. Also you have to buy another tin of gunk. So I've ordered a space saving spare wheel and a bag to put it in. It comes with a jack and wheel brace, but I'll use the tommy bar and socket from my old socket set. I also have a big ring spanner that I can fit on the end of the tommy bar, which will give me more leverage, if the wheel nuts have been overtightened by an enthusiastic service engineer with an air spanner. It can go in the boot, or in the foot well behind the driver's seat if I need the boot for something else, the proximity of the back of the driver's seat will stop it rolling about. The boot is very small. But I bought a boot tray and a roll up rubber mat. To protect the backs of the rear seats when I've got my golf gear in the car. There'd still be room for it back there. I'm hopeful I will always have possibly wasted my near £150 and never have a puncture, but I'd rather be safe than sorry.
All cars have a spare but it's an itty biity "can't drive over 25 miles on" tire. Looks like a big wheelbarrow tire. When I had my Ram truck I kept a spare underneath that was a normal tire but never had to use it.