When I was buying my first home, at first I was trying to go without a buyer's agent. I had to call each seller's agent and schedule a showing with him/her; they wouldn't just give me the passcode to get the house keys. Then they would give their spiel to us while showing the house, and you could tell they didn't want to give complete answers. Sure, if you're only looking at a few houses and already have a decent amount of experience, this may not be a big deal. I thought it'd be easy, but after looking at 10+ houses this way and still none that we 100% wanted to buy, I found a seller's agent. He was recommended by my boss and was worth it. We ended up looking at many more houses and he made it a lot easier. He had 30 years' experience in the area and knew the market really well, including the quality of neighborhoods. He also got to know our preferences and ended up finding our first house right when it went on the market. We've recommended him to everyone and used him again when buying our 2nd home (the 1st home was great but I decided to downsize and move into town after living there for about 5 years). Each time we looked at probably over 30 houses with him. He gets most of his clients from referrals; we were a referral and he has gotten at least 3 successful referrals from us.
One house we really liked during our first experience was an old farmhouse on what used to be a dairy farm; it was now a 3-acre lot and a good price. We had previously looked at it with the seller's agent and had it on our original short list. When we walked in with our buyer's agent, he said, "all the floors are sloped", and once he said it, it was obvious. He found a lot of other issues in the foundation and the rest of the house that we didn't see the first time, so we decided not to buy it. If not for that, we may have bought the house.
As for using inspectors, since we got to know our realtor really well and knew that he wasn't just in it to take our money and relied on referrals for his business, we trusted his judgment with inspectors each time. Our first one was particularly picky, which was good for us. Our second one was also pretty picky and found a lot of stuff; our buyer's agent even found a few things and negotiated the seller paying for the fixes for us.
So all in all, with the realtor we had, he was 100% worth it. If I were retired and knew the market well I would perhaps change my mind, but being a working stiff and with no RE experience, I am glad we went with a RE agent. A coworker was trying something similar (going on his own) and was getting frustrated so he ended up using our RE agent too. Like someone upthread said, it's like dating: you don't marry the first one you meet. It took a bit of asking around before finding one we really liked.