My low point drains consisted of angle valves under the kitchen sink terminating with open PEX under the trailer. I added the following fittings to each. A Flair-it 1/2 PEX x 1/2 male pipe thd fitting, 1/2 female pipe thd x 3/4 male garden hose fitting and a female garden hose x quick connect garden hose fitting with built in ball valve. I can close the ball valves and open the low point drains valves under the sink. This allows me both hot and cold water connections outside.
I can use each independently to fill a bucket, connect a hose with sprayer for hot or cold water or use washing machine hoses to connect a laundry sink with faucet for some serious outdoor washing and cleaning.
In the winter when not being used I close the valves under the sink and open the ball valves under the trailer so the tubing outside doesn't ice up.