To answer your questions re: NS Laredo SC…
2. Closed Cell Foam
3. Yes, heated gray tank (the 40 gallon fresh water tank is in the cabin beneath the step)
4. Yes, you can delete all if you want.
5. 4-season package includes foil insulation in the ceiling, walls, and beneath the floor. Well worth it for about $150.
We really like our Laredo, however, if we were to buy again we would buy a Laredo clone through BundutecUSA, which is also based in Iowa. The main reason why is because they offer the Truma Combi combination water heater furnace. This saves on a tremendous amount of storage space and is more efficient electrically. I would also upgrade the electrical system to include an integrated inverter with a transfer relay.
Bundutec’s owner, Rory Willet was a part owner at Northstar for many years and builds his campers essentially the same way as Northstar with several improvements including aluminum siding, better cabinets finishes, and the aforementioned Truma Combi. BundutecUSA is more amendable to customization than Northstar, too.