OK, I understand that licensing is done on a per user bases. So with up to 5 installations per user theoretically one subscription would work. But my mother wants to be sure everything is done legally, so here’s a list of the the computers that need it:
Church Computer: Mother is the only regular user
Home Desktop: Mother is only regular user
Home Laptop: Shared by Mother and Stepfather
Work Desktop #1: Stepfather is only regular user
Work Desktop #2: Mother is only regular user
I’m assuming they need two subscriptions to the “business” version. Does it matter that they both use the home laptop?
Personally id just use google docs, free office.
As for this, seeing as your mother uses 4 of the computers, then installing one office on them all is legal as you can get, as its 5 per user. So really you only need 2 right?
Three to four licenses. The church should pay for it. I understand that your family might have compassion for the church, but the church should legally pay for what they use and as someone who did youth group and did stuff for his church, I would not volunteer again what I did. --Off my pedestal.
Home computers, if they have Windows 8 or above, and this might be an option for Windows 8, you authenticate with MS for the user login. For 365 you most certainly authenticate with MS for Office. So, it might work, with two desktops and two accounts, and one 365 but I kinda doubt it. You’ll be hassled by a lot of nag screens on logging in. I imagine they’ll have a hard time using Office at the same time.
Work computers… Is this self-employed or a business? The business (if not self-employed) should pay for it. But, you’ll fall into the same issue as the above case scenario. You login in, authenticate to MS, both use Office at the same time and both authenticate - issues.
So, re-thinking:
Church - 1 license that church pays for
Home 1 & 2 - doubtful you’ll both be using Office at the exact same time, 1 license
Work 1 - 1 license
Work 2 - 1 license