You can build a really decent SFF pc (small form factor) with Mini-Itx parts that is like the size of a toaster.
Id suggest an intel i5-8600k, 8gb ddr4 ram, z370 motherboard (has to be 300 series for this cpu) and like a gtx 1050ti. 400watt powersupply and some mini-itx case. Should be under $1000