We live in a 3 story, 4700 sq.ft. house. Our 4 year old State Select 75 gallon gas hot water heater is located in an unfinished (but heated) area of our basement. Our main bathrooms and showers are on the 3rd floor. Our problem is that when we turn on our shower, the water hardly gets warm, let alone cold. However, after wife takes her shower and I get in, the next batch of water coming in is much hotter. Trying to figure out why the hot water for the 2nd shower is so much hotter and why we aren't getting enough hot water for the 1st shower. Similiar situation for tub. Wife will try to fill master tub and it runs out of hot/warm water during filling (even with a 75 gallon tank). However, if she gets in and waits about 10 minutes, the water that comes out is much hotter. We keep our heater set at a fairly high setting to maintain enough hot water for that first shower in the morning. Can anyone offer assistance if it appears that the water heater is behaving normally or if there might be something wrong and what to have a technician look for. Also, since it's a 75 gallon tank, I'm wondering if we really need such a large tank. Our builder put it in standard, but could we get by with just a 50 gallon tank and would we save much money? We have 5 people in our house, 2 adults, 2 teenagers and a 6 year old. We rarely shower at the same time, nor do we seem to multi-task except for maybe running the washing machine and dishwasher at the same time. Any thoughts would be appreciated.