Bicycles Stack Exchange prohibits recommending products, but we can offer principles to use when shopping.
The key to choosing the right bicycle is matching the bike to the kind of riding you want to do. I apologize for the length of the post - this is a complicated topic.
Generally speaking, you can narrow your search to just a few bikes by:
- Identifying the type of riding you want to do
- Match a bike type to your need
- Select a brand of bike
- Filter for bike type and your price range
Matching a bike to your need
Starting with the beginning of the decision making process - you may have already thought all this out but I want to be thorough.
Bicycles are designed for different kind of riding styles. Bikes are like shoes; there is a different shoe for every activity.
Looking at one bike maker's website offers examples:
- Cross Country
- Cross Country/Downhill
What's the difference?
The different types of bikes are designed for a type of activity, most of the names are pretty descriptive. What's different about each type are things like:
- Frame geometry: this will determine how the bike rides, handles, and the seating position
- Tire size: generally narrow tires are faster and less comfortable, wider tires are slower and offer more comfort and/or more traction for off-road
- Appropriate drive train / gearing for the task
- Appropriate brakes for the task
- Wheels to match the application
In the original post the type of bike mentioned is "sport/hybrid". This style of bike indicates that the bike
- Will be used on streets or paths
- The rider prefers a more upright seating position
- Tires in the medium-wide to wide range for greater comfort
- Focusing more on comfort than speed
If these qualities match the kind of riding you have in mind then you have selected the right bike type.
The original post mentions some specific parts. My thought is that some of the parts are "must have" (meet a riding need) and other parts are "nice to have"
- Triple chain ring: this feels like a must have given the hills described
- 9 speed cassette: if you found a great deal on a used bike with a 7 speed cassette would walk away? 21 speeds will give you plenty of gear choices.
- hydraulic disk brakes: nice to have. Any quality brake system will get you stopped on hills.
- 700C tires: for the riding style described the tire width seems more important than the wheel diameter. Do you want 40mm wide tires? Wider or thinner? If you find a great deal on a used bike with 26 inch tires is that a deal breaker?
- Carbon fork: seems like a nice to have
Selecting a brand
Major bike makers are very competitive with each other in each type of bike and at each price point. Every now and then one maker introduces something that gives it an edge over another maker. Usually, it's only a perceived edge and not a measurable edge.
All that to say - in a given category and price point bikes are very similar.
The one large exception are bikes sold in department stores. Department store bikes are built to hit a very low price point and large compromises are made in quality of materials and workmanship to achieve a low retail price.
One way of narrowing your brand choice would be to look at parts availability and support.
The original post indicates a desire to purchase a used bike.
Evaluating the condition of a used bike is easier than evaluating a car but it still takes some bike knowledge to do a good job of evaluation. Here is a link to a previous question on buying used bikes with some helpful answers.
Even if you are looking for a used bike, drop by your local bike shop. A good shop is interested in helping people learn about bikes. They should be happy to answer questions and let you test ride a few bikes. The test rides are critical to verifying that you are looking at the right type of bike.