Grays I believe are 30 to 40 gal,i know on my outside kitchen the tank is very small,usually after 1 day of kids washing hands its full.Sorry I don't know exact numbers. I just looked at this same trailer Saturday but a north point with the 2 bathrooms,beautiful trailer by the way! I would say your bathroom sink and shower go to 1 gray and kitchen goes to its own gray tank if you have 2 gray valves. Outside kitchen also has its own like mentioned.
06 2500 Duramax. Air lift 5000 air bags,Equalizer WDH, EFI live,fass fuel system,4" straight pipe
2015 Jayco Eagle Premier 314BHDS
IBEW local 94 Electrical Worker