Try any of these and  you won’t be disappointed. They vary merely in perceived levels of luxury, not the important stuff like warmth, comfort, clean sheets, great shower facilities, no mozzies etc……
This is by no means an exhaustive list, so look around!

The last two also come with a diningroom, coffee, delicious breakfast, etc.

The Overkaroo Inn
The Karoo Moon House & Cottage
The Karoo Art Hotel 
The Sorgvry Guesthouse