My Grand Design trailer was so simple and convenient. THREAD the hose onto the city water connection, then turn a handle to select "City" or "Fill". AND it was on the utility (driver) side where it should be.
Since my fresh tank is on the passenger side, even though inconvenient, it makes sense to put a gravity port on that side. But it wouldn't have been that much more to install a small locking compartment with the city water connection and a two-way valve.
To me, it's small low cost details like that which provide value, and separate the desirable coaches from average ones.
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