6x4 be ok
That will be too tight. The Book of Geese Dave Holderread rec 7.5-10sq ft of floor space per bird.
My goose house measures 77"X52" It was originally for 2 geese then I went and got 2 gosling for my pair which brought it up to 4 geese in this house Which gives my geese 7.32sq ft each. They seem to have plenty of room are not touching each other [geese don't like to touch when sleeping] and I have a back up goose house in case I have to separate my 2 pairs when breeding get under way. If you plan on gosling down the road I'd build as big as you can.
yes as long as he doesn't decide to add more geese . you know how we are. lol