1. Check the fit, not just the build volume
Install the manufacturer's slicer and load those models into the exact printer profile. Do they fit in a sensible orientation? Is there room for the supports or brim you need? Would splitting the largest object into two pieces be acceptable?
Then measure the place where the printer will live. Allow for the moving bed where applicable, spool holder, open door and access for maintenance. A machine that fits on paper may still be awkward to use on your shelf.
2. Buy for the materials you will use
For ordinary PLA and PETG projects, an enclosure is not automatically a requirement. Materials such as ASA and ABS benefit from a more controlled printing environment. Check the exact printer–filament combination rather than treating a high nozzle-temperature limit as proof of compatibility. Prusa's material guide is a useful starting point.
Placement and emissions control are a separate question. Do not assume that a closed box makes ventilation unnecessary; plan the workspace before buying. NIOSH's 3D-printing guidance explains why source control matters.
3. Compare the work around the print
Open the maintenance guide before opening your wallet. Can you find the nozzle-replacement procedure, spare build plate and troubleshooting instructions? Check local parts availability and the warranty terms for your region. Maintenance is part of ownership, not evidence that a printer is defective. UltiMaker describes the main maintenance needs here.
Auto-leveling is useful, but a dirty plate can still spoil the first layer. Look for clear setup instructions, not a promise that calibration removes every failure. Prusa's first-layer guide separates these causes.
4. Treat speed as a question, not a ranking
A headline speed does not tell you how long your parts will take. Small moves may never reach it, and acceleration or material flow can impose lower limits. Speed settings and volumetric-flow limits explain the difference.
Use the three models to compare sensible quality profiles. Keep the layer height, walls and support choices comparable; regard slicer times as estimates, not a benchmark test.
Our buying rule: choose the least complicated machine that handles your three projects and has support you can use. Keep some budget for filament, storage and replacement consumables. Add multicolor capability when you have a project that needs it—not just an empty accessory slot.