I can buy natural gas on 6 and 12liter tanks, but no natural gas network (we export 99.9% of it). I would have to install a chimney/exhaust and run some plumbing and that sounds like an extreme undertaking for one or two winters, at most three winters.
Insulation will happen as best we can.

So what do you use in your workshop by the water Gato? Or dont you use it during winter (it is a lovely workshop, so that would be a pity).