I have an old house (built in 1898) in a little farming town north of Sacramento, California that I am restoring and would eventually like to move there. There is a little guesthouse attached to the garage in the back. The property has old galvanized steel pipes for the main water line from the water meter in the alley to the house and for the lawn irrigation. The lawn sprinklers have the old manual brass valves with Champion metal sprinklers. Galvanized steel pipes are also used for the water and a gas line from the gas meter next to the house to the little guesthouse in the back. It is time to replace the galvanized metal pipes because both the gas and water lines are failing. They are corroded, rusted and pitted. I would like to go into this project informed with some idea of what to expect before I reach out to plumbers for bids to run the lines from the meters to the house and guesthouse. I am fortunate that I have a friend who is landscape irrigation designer that will help me with the design of the landscape irrigation. The plan is to put in drip irrigation, rotator head sprinklers and a control panel to automate the watering. Up until now I have not been able to put in any new plants or trees because there is no automated irrigation system so in the summer they cannot be watered during the week. I will ask the plumbers putting in the lines to stub out an irrigation line for the irrigation system to be installed later. My questions are: Does the water line from water meter to the house have to be a straight line with no turns in it? What is the recommended pipe material for a water line? What is the recommended pipe material for a gas line? Anything else I should be aware of when putting in new water and gas lines? I would greatly appreciate any advice. Attached is a photo with a view from the water meter in the alley. You can see the main house and the little guesthouse on the left.

When we had the house built in 2013, they told us that the basement was roughed in for a bathroom. I know what some of the holes are and have an idea on the two PVC pipes, but I am confused at what is missing. In the attached picture, I know what the blue squares are for, but I'm not 100% on the red. I thought a vent for the tub/shower or the toilet, but there is no pipe above to connect to(the confusion). Any help would be greatly appreciated.