A budget title in its core with a pretty mainstream following.

+ Very good balance between simulating real work and simplifying it in-game
+ Lots of vanilla and licensed cars to work with
+ Your shop can be expanded in many ways
+ Game forces you to be wise with your money choices at the start
+ Junkyards and barns to find old cars and used parts for cheap
+ Warehouses to store and organize parts the way you want *1
+ There are no time limits after you accepted a job
+ Basic actions can be done outside the garage too (oil change, body panel removal, etc.)
+ DLCs not necessary in order to complete the achievements
+ Steam Workshop for those who want even more content
+ Runs well on weaker graphics cards (GTX 1650)

- Any action involving driving is implemented rather cheaply
- Fixed camera position when refilling oil and other fluids (parts might be in the way)
- Older cars (even supercars) often come in way too rusty and damaged *2
- New individual body parts always come in black *3
- There could be more garage customization options, you also cannot move to a different location (your workshop is situated in the desert, pretty much in the middle of nowhere)

*1 The game offers up to six virtual warehouses outside of the inventory (which is available from the start, unlike the warehouse upgrade). Within the game, it's just a small room with shelves and random boxes on them. You cannot see or interact with the parts in any way, which is a bit unfortunate.

*2 Imagine owning an XJ220, having half the car broken and completely covered in rust, yet you just want an oil change from the mechanic. In general, you recieve many cars that look like complete wrecks which shouldn't be allowed on the road at all. It looks pretty hilarious on some of the DLC cars that are very expensive in real life and would never make it to such state. I'm pretty surprised the licenses for real cars even allow it to begin with, given how sensitive certain auto makers are when it comes to their cars getting damaged virtually. Well, no problem seeing it here (though to be exact, you are there to repair them instead of wrecking them further). There are a few story orders where it's described as a car accident, so I guess it makes sense there, but you get these wrecks way too often in normal orders too.

*3 There is an option to re-paint these parts if you've got the paintshop fully upgraded, however there's no option to match the color with the car you're modifying (or at least load the color information from somewhere), therefore it's rather useless as far as fixing cars goes (I guess it still makes sense for visual tuning of your own cars that you want to sell later). Thankfully, the game never wants you to achieve this, but it kinda ruins realism yet again as you can send back a completely mismatched car and it will be accepted.

Game was reviewed based on playing in normal mode. There's a simplified mode and also an expert mode, which (if I recall correctly) gives double the XP and doesn't offer hints of broken parts. You cannot change the career difficulty afterwards (there's more profile slots though). I also haven't played CMS 2018 to compare between these two versions, just CMS 2015 over which CMS 2021 is a big step forwards.

CMS 2021 is further improving on the previous installments, should run fine on any modern gaming computer and time flies when playing it. Very easy to recommend. DLCs are not necessary, buy only the cars that you truly like and want in the game. There's also the workshop if you don't want to rely on official licenses. All the issues listed here are pretty small, none of them game-breaking or something that would completely ruin the experience. You also need to take into account that it's not a AAA game.

8.5/10