I am about to buy a new bike. Not a second hand one; a brand new. I am looking at specifications and webshop prices to get an idea about what should and could buy, but the spectrum is too wide to check every single one in a shop. I noticed, that most brands have models with different components, and the maxed-out version is 3-4 times more expensive than the cheapest one. There are minimal differences in function, but not on the price tag. Like this cross bike: Kross Evado 1.0-7.0. Local brands tend to be cheaper, but they do not have high-end machines on their palette, so I am a little bit concerned about the quality.
Most LBS here sell 2-3 brands only, so it's really hard to do a side-by-side comparison in real life, and I am not too familiar with component levels.
What is a good heuristic to find the best value for my money? What to look for when comparing two bikes by their specification only?
(To be more specific: I am currently looking at hardtail MTB's and cross (hybrid?) bikes, mostly from the lower end. I think I know my preferences fairly well, but I've never had a bike with discs or suspension and do not know what to look for.)