water($20), nutrients ( $200), Water Pumps ($100), Depending on style of hydro...DWC, E&F, NFT, you will need Reservoirs ( $20-$100), tubs ($100) Air pumps and air stones ($80). TDS meter ($100) PH meter ($15-150), seeds ($50), rooting medium ( $30) , tubing and hoses, valves, net pots. ($50) and your going to need some good lights ($300-500).
So if you want to grow a good amount of bud with quality results expect to pay over $1000 to get started.
Wanna go hydro on the cheap with just 1 plant ( Female)? Get a 5 gallon bucket, fill with Ph 5.6=5.8 water, put an airstone in bottom connected to air pump. cut hole in top big enough for net pot to fit snugly, fill pot with rockwool and transplant your sprout into the rockwool. Give minor amount of fertilizer to begin with. change water out to new water each week, maintain PH 5.6 or so and you are now growing DWC, or aka Bubbler. You still need a light though, dont skimp on that it makes the biggest difference.
Also try reading this a few times
https://www.rollitup.org/view.php?pg=faq