Oh my, that's a lot of potatoes. We always have a big bowl of potato salad for family gatherings, doesn't matter the season or reason.
Have you ever heard of Funeral Potatoes? Usually made with frozen shredded or hash browns, I think you could do it by weight as well.
I call them Souper Potatoes, goes over better
One Largish Package Hash Browns (I think about 1.5-2.5 pounds)
1 can Cream of Potato Soup
1 can any other Cream soup, can be Chicken, Asparagus, whatever you like
1 16 oz sour cream
Optional:
1 stick butter
1 onion
or
shredded cheese (1-2 cups)
can also doctor up with bacon, canned jalapenos etc.
Spread potatoes (still frozen ok) in large rectangular baking dish
Chop onion and saute in butter, pour over potatoes
Spread soup mixes over potatoes, swirl a bit or add some milk (1/2-1 can) and pour it over
Back at 350 for about 60-90 minutes.
One of the reasons this is called Funeral Potatoes is it holds its heat forever and can be taken to potlucks and such.
Here's a larger non-soup version on my usual recipe site (cooks.com)
https://www.cooks.com/recipe/b76qk4t...-potatoes.html
I'd say that would be about 3-5 pounds of potatoes and great for your Saturday group.