I am very close to buying a 3D printer and have started to do some preliminary design work from the things I'd like to make, but I have a question: Which corner of the print bed corresponds to the origin (0,0,0) in slicer software? Is this the same across slicers and printers?
The reason I ask this is because of the difficulty some have in removing items from the bed. It seems to me like I'd want to print small items closer to the front of the printer to make access easier, but it looks like most slicer hosts only show a box representing the build volume with no real indication of what's "front".
Depending on what kind of printer you have, the build table origin and slicer origin (0,0) are usually either the front left corner, or the center of the build plate. This can be changed by the end-user in most open-source printers. There is no standard or requirement for a particular origin location. The important thing is merely that the slicer and printer coordinate systems match, so parts actually come out where your slicer thinks they should.
In practice, it's usually quite easy to tell what's "front" in your slicer's build volume. When you open the program, the bed usually appears as it does when you stand in front of your printer. It is rarely an issue.
In terms of difficulty removing prints from the bed, a removable build plate is an excellent solution. Plastic has a higher coefficient of thermal expansion than most build plate materials (like glass), so throwing the print+plate in your freezer will generate large separation forces and help remove the part for you. Non-removable build surfaces are a deal-breaker for most serious 3D printer users I know. Either don't buy such a printer, or add a removable plate yourself.