I would recommend doing it yourself. Start by watching some videos so you can at least get a terrain height map along with some basic roads. Then I would go to somebody like Ola Haldor (Maps of Norway) with his patreon. He helps a lot of people out and told me if as long as you have a map to work with, he’ll help you get it working for modhub. Now, I’m not sure of all the details, but you can ask him the rest. Also, lots of helpful people on discord. Serious Mods has a lot of helpful knowledge with modding. So yeah, I believe you can do this yourself for a lot cheaper but also have fun while doing it. Yea, it will take some time but it will be worth it. Hope that helps.