I'll take tips and advice on guineas or chickens! I need all the help I can get! We live on 28 acres, so I've got the room. I do have one cranky neighbor...but he'll get over it. :/ He's put up with my "surprise" rooster. Everytime "Harry Larry" (was Henny Penny) but then it became obvious that he was NOT a hen...sees the neighbor, he starts crowing. Thanks again.
It would be great to say you need to start with a certain number but the truth of it is you always seem to end up with more. Build bigger than you need, it will seem like a waste now but it will fill up quicker than you think. Better to build big than to have to rebuild like I did. Either you go to pick up feed and find a few "returned" ones that are cute, run into trade days, find something great on this site, or end up like kuntrygirl and have babies popping up out of nowhere.
I only know about chickens not guineas, however from what I have read on this site guineas are loud. Something to keep in mind.
I would look into sand for your coop and fermented feed. I have switched to both, the sand made it easier, cleaner, smell better, and less misquitoes. The fermented feed made my girls happier and more perky. Good links to look at:
https://www.backyardchickens.com/t/444759/got-sand-you-should
https://www.backyardchickens.com/t/644300/fermenting-feed-for-meat-birds
I follow the posts of Kuntrygirl and Beekissed, it started because every time I looked something up I always ended up with their posts as the answers. Both have a lot of really good information out there.
There is too much information for us to tell you (or remember) everything, however if you know what you are looking for we can narrow it down with really good links that helped us and things that we have learned threw trial and error.
Also, why did you get into chickens? Eggs, meat, and showing all have a few different requirements. Basic health is the same for all of them, keep an eye on them, they are like kids most of the time you can tell if something just seems off.