Cheap Yet Safe Enclosure:
https://www.lowes.com/pd/Hefty-25-Ga...Lid/1000505547 $18
Dollar Store Melamine Bowls (2) $2
UTH, Thermostat, & Thermometer (don't skimp on these):
http://www.reptilebasics.com/ultrath...ter-uth-11-x11 $20
http://www.reptilebasics.com/ve-hobbystat $70
http://www.reptilebasics.com/TG-1 $20
Hides: Get some of the Ramen meals that are around a buck apiece and come with the plastic containers. Eat the food (cheap lunch), run the container through the dishwasher, cut off a corner of the container to make an access hole, and you have a hide for a baby snake for $1.
Substate: newspaper
Even with tax and shipping you're all in for under $150 and that setup will last your snake for life; you'll just need to upsize the hides as your snake grows. Clutter up the tub with excess hides or newspaper so the baby has hiding places until it grows up.