If you plan to grow inside and not outside in nature i hate to say it but if 40 $ is to pricey then you might want to reconsider starting to grow right now and save up some money. This is a hobby like anything else and requires start up cash. I always recomend atleast 200$ for the bare essentials to start then get fancyer as you go along. If even 40 4 is to much for you to spend right now your harvest will be disapointing at best.
this means you will be half assing ( possibley even 1/4 assing ?!?!? ) the light set up the seeds the grow medium the soil and the nutrients. This would be much like building a house with out the funds for wood or nails. your just gonna end up with a bunch of stuff tied together with string.
heres a good cheap set up
1) 5 3 gallon grow bags + pro mix soil to fill them 30$ ( do a google search for plant / hydro shops near you they will have this )
2) general hydroponics maxi series dry nutrients 1 lb maxigrow (veg ) and 1lb maxibloom (flower) 27 $ ( 12- 14 $ each) ( order if off ebay or pick it up at the same store u get the dirt and bags from )
3) 5 feminsed seeds from nirvana shop around 40 $
4) PPM meter off ebay to measure the amount of nutes your feeding your plant ( they are 14 $ on ebay and like 60 $ anywhere else so use ebay for this ) ( this is also an optional item but its makes life easyer and its definitly worth the 14 $ but alot of people grow with out them so its personal choice )
5) refurbished 400 watt MH / HPS grow light with 3 year warentee ( search insidesun on google the have them for 125$ shipped which is 100$ cheaper then a new one and it works the exact same way save your self some cash ) ( another option is a 150 hps / mh lamp from econo lighting which is i think 20 $ ) I use 2 of the 400 watts from inside sun my self and they work great. I have no experience with the econo lights but some people on this forum can tell you more about those
all added up right around 236 $ and if you folow the instruction and guidence of the people on this site and do your own research you will have 5 very beautiful healthy female plants which can yield you several ounces. which last i check in my area 236$ wouldn't get you an ounce of chron is your life depended on it. so it pays for it self. Also once you get your first harvest done you could potentially sell part of it ( im not suggesting this but you could ?! ) to make up for your invested cash and maybe even a little more to expand your set up with better nutes, a home built or store bought hydro system, Co2 supplement, grow tent the list goes on for ever i hope this was helpfull. i am not trying to burst your bubble here i am just trying to make your first harvest a successfull one and not another story on these forums with a 14 inch plant with 3 nodes in a dixi cup under a desk lamp