Casing is very personal choice. Some willing to only spend $30 case, some see what has been included with the case, some would see the looks of it, while some would see the construction of it and pay top dollars $9xx for a case.
Cheap casing usually their construction are quite flimsy. They do come with a lot of flex when it is being carried by the frame, or perhaps 0 cable management area, or perhaps non removable hard disk cage. Mainly made of cheap thin steel and many areas are bolted with rivets, so modding it wont be so easy. Comes with or without tempered glass. This is an example of $30-$50 case range.
The mid budget segment is usually from $51-$99. This category involves value. They usually use the same thin steel construction as the budget segment. Easy to bend. But this category will just throw in more fans into the case. Although nothing to brag about the fans, cause usually this segment the case fans are rubbish to begin with. Usually low rpm, unable to pull in more air if there is a restrictive front panel, and usually do not have high static pressure. Cable management place is a little better but nothing to brag about also. Cheap ITX case can be found here also.
Things start to get a little more serious in mainstream segment, between $100-$179. This segment is where most people willing to spend. This is where steel case gets tougher. Some comes with great cable management area and also the ability to remove hard disk cage. Some even have unique psu shrouds to hide those hard disk and also other ways to show off your rig such as ssd mount, some rgb around the case, comes with fan controllers or led controllers. Some case even give you good static pressure and airflow fans. Good ITX casing can be found in this segment.
The next is mid high end segment $180-$299. This is where people willing to spend on expensive case and wants everything included. This is where steel construction case gets even thicker and stronger than those mainstream segment. From the frame to front panel to even the mobo tray. Apart from that you do see entry level aluminium case starts to step in. Usually for cases at this segment do have unique cable managment area. Some have great ways to cover the hard disk and ssd, some has premium fans included, some even go till the point that the case is tool-less to work with.
$300-$599 this segment is high end segment, some are aesthetically inclined rather than functionality in mind. This is where most cases are made out of aluminium instead of steel. Of cause there are steel cases, but they are called the super towers, large.... yes its huge, so tall that it is the height of your waist. Aluminium case like lian li and inwin, it is super light, yet VERY sturdy and strong. Usually this segment cases has no fans included. You have to buy your own fans, cause if you buy cases like this, this is where people would buy their own fans.
$600 to the sky is the limit..... this is ultra segment lol. This is where pcmasterrace godlike people willing to spend. Or rather see it as a piece of furniture in the house.
Personally i started out using coolermaster elite 120, till i change to this few.....
- Sharkoon T28
- Corsair Air 540
- Corsair 900D
- Phanteks Enthoo Evolv
- Lian Li O11 Aluminium
- Inwin 909
- Lian Li O11 Dynamic
So yeah. A taste of every segment lol.
