Some bottled water is expensive. Some is extremely inexpensive. By the way, “Evian” (as in the name of one bottled water product) spelled backward is “naive”. Think about it.
If you’ve never tasted any water other than the tap water at your home (and you’ve never moved), you have no idea what tap water should taste like. The best way to find out is to drink bottled water certified to be pure for a couple of days. If the tap water still tastes okay to you after that, then it will probably always taste okay to you.
When I was growing up (until the age of 13), I lived in the little podunk town of Coolidge, Arizona and the tap water tasted fine to me. I didn’t know any better. When my family (my parents’ family) moved to a suburb of Kapaa, Hawaii, the tap water tasted different, not necessarily better. When we returned to Coolidge around three and half years later, the Coolidge tap water tasted horrible. We could taste the chlorine added to it.
When I bought a house in Phoenix, Arizona (while I stationed there with the Marine Corps), I tasted the tap water and immediately had a water softener installed in the garage and a reverse osmosis tank installed under the kitchen sink. I don’t think I made my money back on it until I sold the house (for far more than it should have been worth) twelve years later.
I didn’t have to deal with hard water stains in toilets and showers, using too much laundry detergent and various other things because of the soft water. The tap water, run though the reverse osmosis tank at about a gallon per hour, was always delicious. So much so that my wife’s “friends” would come over and get gallons of it from us. (Damn those moochers.)
When me, my wife and my younger son (Jonathan) moved to Olongapo in 2006, we had bottled water in 5-gallon plastic bottles delivered to us. It was inexpensive at around $4.00 USD for 25 gallons (94.64 liters). It was safe to drink - the owner of the company used the same filtering system I used in Phoenix.
I bought a bottled water dispenser shortly after moving into our house and I only had to replace it once. The replacement was thrown away when we left in 2018. The dispensers, regardless of the brands or prices, tend to be cheaply made and designed to last no more than five or six years. Most of them were made in China.
I returned to Phoenix in 2013 and the three of us lived in a seedy apartment until Jonathan joined the Army. We left for the Philippines the same day his leave (after AIT) ended in 2014. During that time, we drove to a nearby Circle K store and got our bottled water from a Glacier machine. It had a 5-stage filter system and it cost us 25 cents a gallon. As inexpensive as that was, it was still cheaper to have it delivered in Olongapo.
When we started our long term vacation in Florida in 2018, we found our older son (Joseph) using a PUR pitcher for water filtration. I tasted the tap water and I could taste the chlorine. I like to drink coffee and I refused to use tap water for it. Joseph only had to buy two replacement filters while we were there.
When we arrived in Hawaii this year, I tested the tap water and it tasted fine, meaning it had no taste at all.
We live on a military reservation in a rural area (still considered Wahiawa), next to one of the Dole pineapple plantations. The tap water tastes fine to me, but is it safe to drink? If you read a website like the one from the Environmental Working Group, you wouldn’t think so. It’s misleading.
There are good water testing kits available - I can probably find dozens of them on Amazon.com but I won’t waste my time. The EPA tests the water sources every quarter and local government authorities test it on the military bases. If it isn’t safe to drink, we’ll hear about it immediately.