The cost to make a lowest-tier robot with a disk reader, an upgrade slot, and a card slot:
(specific components: [Tier 1 everything, where it matters]
- Upgrade container, disk drive, card container, keyboard, screen, inventory upgrade, graphics card, CPU, Memory x1, Hard Disk Drive)
(a disk of OpenOS was also crafted that can be used in other computers)
Gold: 1 block, 3 ingots, 1 nuggoet
Iron: 7 blocks, 2 ingots
Redstone: 8 blocks, 7 dust
Wood: 1 stack + 6 planks, 1 stick
Stone: 1 stack + 9 blocks
9 clay blocks
9 cactus
1 sand
1 leather
3 string
Less than 1 coal block (for generator fuel) (assuming ores are already smelted but cactus isn't)

A turtle with equivalent capabilities in ComputerCraft:
7 iron ingots
8 planks
7 smoothstone
1 redstone
1 glass pane