@Molynoox "soonish" I would suggest your going to be looking at several years to get going, how many have you projected to have to do in a year? Perhaps you could broaden you range of offerings, look at Breeze houses for instance, & as
@mikej460 linked to, explore the outdoor life style options, not everyone wants a home office, I will consider anything to keep my order book busy, within limitations though.
We have, over the years done: outside rooms/kitchens/BBQ areas/car ports/porches/bars/stables etc and even things like log stores, as well as our Joinery side of things, I keep an open mind, but we make everything offsite which is a massive benefit over standing in a field in all weathers!
Digital marketing isn't a world I operate in, but, its powerful, I find that all my clients use it in all its forms, (generally in the age range of 30 to 65) my outdated web site is miles down the ratings but people still find me. I've never advertised in print, I don't want to get bogged down with answering fruitless inquiries, I get enough of them already, as I mentioned before a local "
Garden rooms" business near me, also has a fully liveried van, which is an ideal marketing tool.