Juli Clover writing on Mac Rumors:
Many have speculated that the Mac mini also includes soldered RAM, which has now been confirmed by Macminicolo’s Brian Stucki. According to Stucki, the RAM in the Mac mini is “not user accessible,” which means those who purchase Mac minis are limited to 16GB of RAM that must be upgraded when purchasing the machine from Apple.
All three Mac mini models can be upgraded to a maximum of 16GB of RAM, with the upgrade priced at $300 for the base model and $200 for the mid and high-end models.
The Mac mini was not only an excellent choice as an entry-level desktop Mac, but it also worked as a great upgrade-later machine. I’ve recommended the Mac mini to many of my friends who bought it as their first Mac and went on to upgrade the RAM & HDD after purchase.
Now, not only can you not do any upgrades after purchase, but you can’t even order configurable options in India, so you’re stuck with the three standard models as your choices.