If you can I would return the system and get a SSD only model instead. If thats not an option then
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If you can I would return the system and get a SSD only model instead. If thats not an option then...
The next best option is to get an external Thunderbolt RAID drive like either of these: [https://eshop.macsales.com/item/OWC/TB2U3MED0GB/|OWC - Mercury Elite Pro - Dual drive] or [https://eshop.macsales.com/shop/Thunderbolt/External-Drive/OWC/ThunderBay-4-mini|OWC - ThunderBay-4 mini - Quad drive] and add in your own SSD's.
As your system is so new I wouldn't opening it up as you'll loose your warranty. But if you are willing then you'll need backup your drive first, then break the Fusion Drive set before you open the system following this IFIXIT guide: [guide|95631|iMac Intel 21.5" Retina 4K Display (2017) Logic Board Replacement] The issue is you need to pull the blade SSD and get a replacement. Your current SSD is only 24 GB which is quite small. Once you replace the SSD with the larger SSD you should be fine. Now the Rub! Getting a larger SSD will be expensive as well as hard.
Which is why I think given of the issues here it is smarter to go with the external drive.
mmm... At this point I think you are a bit stuck.
If you can I would return the system and get a SSD only model instead. If thats not an option then
The next best option is to get an external Thunderbolt RAID drive like either of these: [https://eshop.macsales.com/item/OWC/TB2U3MED0GB/|OWC - Mercury Elite Pro - Dual drive] or [https://eshop.macsales.com/shop/Thunderbolt/External-Drive/OWC/ThunderBay-4-mini|OWC - ThunderBay-4 mini - Quad drive] and add in your own SSD's.
As your system is so new I wouldn't opening it up as you'll loose your warranty. But if you are willing then you'll need backup your drive first, then break the Fusion Drive set before you open the system following this IFIXIT guide: [guide|95631|iMac Intel 21.5" Retina 4K Display (2017) Logic Board Replacement] The issue is you need to pull the blade SSD and get a replacement. Your current SSD is only 24 GB which is quite small. Once you replace the SSD with the larger SSD you should be fine. Now the Rub! Getting a larger SSD will be expensive as well as hard.
Which is why I think given of the issues here it is smarter to go with the external drive.