disclaimer: I haven't checked this for a couple of patches - not certain if anything has changed, this was based on only 1 attempt each
clockwork scorpion: clockwork scorpion assembly, 100 bronze ingots, 10 gears (30 stones total weight)
1 follower slot
51hp/78 stam/- mana 89/78/17 67.1 barding
resists: 22/15/23/43/13
base damage: 5-10 (60% phys, 40% poison)
skills: 60.4/68.6/33.1/0.0/91.8(poisoning!)/-/-/-
pack instinct: arachnid
leather wolf: leather wolf assembly, 100 regular leather, 1 flask of oil (provisioner sells this for 8 gp)
1 follower slot
211 hp/104 stam/25 mana 122/104/25 73.5 barding
resists: 41/19/25/13/13
base damage: 9-20 (100% phys)
skills: 59.8/69.5/64.8/0/-/-/-/-
pack instinct: canine
gargoyle pet: gargoyle pet assembly, 50 leather, 25 white dragon scales
2 follower slots
314 hp/100 stam/102 mana 496/100/102 87.9 barding
resists: 57/40/33/40/23
base damage: 16-22 (40% phys/40% fire/20% energy)
skills: 85.4/100.0/97.0/0/-/32.1/22.0/0.0
pack instinct: none