I agree, look on CL and be patient! I got a 20 gallon with hood, light, gravel, 3 plants, a decoration, whisper filter, whisper air pump, bubble wand, stand, magnet tank scrubber, double sided background, net, and gravel vacuum for $40 worth of trade. (I traded some things I listed on CL for her tank). Best was to do it is to post a wanted add in the pet and general section. The lady I got the 20 from replied to my wanted add.
Now my 10 gallon tank cost a bit more because I was impatient and bought everything new. I got the tank and hood at a Black Friday sale for $15, light bulbs for $4, gravel was $13, filter $10 on Black Friday, heater was $20, thermometer for $3, and I made plants from ones I bought at Michales for around $15. So my 10 gallon cost almost double what my 20 was.