InDesign is the key to economy in self-publishing
Possibly the biggest news in publishing for ministries and non-profits is that you can start out free.
All it takes is an iMac or equivalent (Mac or PC) and InDesign
You will need to do a bit of study. It will take some work. But, it can be done easily. The Adobe apps are all available for less than $50 per month. There is also educational and non-profit pricing.
You can do this!