All this is at walmart.
Cheap dark colored tote.
air pump, tubing, and air stones-all in fish area.
Mylar- Emergency blankets in camping section, they call it aluminized polyester. works like a charm!
double sided tape (to stick mylar onto wall or wherever)
Miracle grow (2 types, one for vegg(all purpose) one for flower(bloom booster))
They're so many types of MG you could actually get a lot of different types for more advanced cycles (veg, super veg, transition, flower and bloom)
Digital thermometer and humidity gauge.
liquid PH tester for a pool or aquarium. (had to get a wide range tester from pet store. it reads from 5.0-9.0)
Humidifier
Light bulbs (CFL- 6500k(daylight or bright white)for vegging. 2700k(warm white) for flower.
They have some security HID lights you can convert to work for normal wall sockets, but I like my CFL
The only thing I couldn't find at walmart for a grow op is the net baskets! Had to get big 10" plant baskets at home depot.
That's all I can think of right now, If I remember anything I'll come back
Happy growing!