Steel or alloy wheels

If care is taken not too much damaged should be done. Probably using a beadbreaker has some potential. Using a Jack or the R&R Beadbreaker would cause less damage potentially than Tyrepliers. I guess you need to think about how many flats you get. A lot of the time using a safetysealk kit you can fix the puncture without removing the tyre. Buying five tyres and five rims is not cheap. Why not just buy an extra alloy and tyre if you are that worried. I have six tyres and rims and rotate regularly using all six.

Spinning wheels in mud = scratched clear coated alloys, if 4wding in Victoria especially.

Rocky loose ground, driving over rocks, also dont help alloys, and once you damage an alloy, if it leaks air, its not like you can fix it right there.

The required modification is very easy to run the correct 16" rims, and though it means changing wheels if required, you can always just fit up 16" and leave them on full time, keeping the alloys to up the resale, by looking new when time to trade the 120 in.

For off-road get a good set of steel rims

My issue with 17" inch is that I can't find a suitable off road tyre to fit. Originals are Dunlop Grand trek but puncture easily.

I am seriously considering buying 16 " steel rims and fitting with more durable tyres when off road, then changing back to keep the wife happy when in town.

Any suggestions.