A small vardo, or gypsy wagon, with a half-door, curved roof and interior bed shelves for 4, will carry 3 tons
The small vardo will need a mule or two draft horses, or a team of four oxen.
The platform of the vardo is high, about five feet off the ground, so there is room under the platform to sling barrels. The door is three feet high and two feet wide, and needs to be crawled into for most humanoid creatures; inside the space is about 5 feet high at the side, almost 7 feet in the middle (suitable for a hanging lamp), 10 feet long and 6 feet wide. The sleeping platforms fold upwards, so chests can be put on the floors and sat on during the day, or at the nearer end (sleeping is done farthest from the central back door). There is a small window on the three sides without the door, one that looks out between the drivers, diamond-shaped and 9 inches wide, one on either side, half-circle in shape and 1 foot wide by 6 inches high.
Oh, and obviously the sleeping platforms can double as surfaces for cooking, working, etc.
Color is typically emerald green
There's always a bit of flowered decoration on the wagon for luck and good will. The wheels are twelve-spoked cedar double-braced hubs with steel hooping on the rims, a metal-flange to provide a little spring and two brushes and a bucket for grease provided free. The net tells me a wagon uses a pound of grease per day, that's 16 x 0.12 c.p. for animal fat, or 13 c.p. per week.