Much of the plumbing is concealed, but there are some areas you can check. If the water is off do not turn it on. It may be off for a reason. If the incoming line is slightly rough gray metal with a bulge at the connections, it may be lead piping. Rock the toilets to see if they move. Loose toilets may leak at the wax ring. Turn on two or three faucets at the same time to see if the flow decreases. The plumbing may require all new pipes if the decrease is severe. Look for mixed types of metal and plastic piping. This may indicate amateur repairs. Does the water drain slowly? Water stains around fixtures or on ceilings may indicate active leaks.
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