I agree, dyna gro would probably be my choice. You can find a small bottle online for under $10. A lot goes a long way. Stuff like fox farms and botanicare require up to 2 tablespoons per gallon during flowering. Dyna gro you use 1/2 teaspoon per gallon. If you can only afford one, go with a flowering formula. It might not be ideal, but most flowering nutes have enough nitrogen to get you by during the whole grow. I can't remember if I called or emailed, but dyna gro actually sent me a small 8 oz bottle of their veg for free. Been using it over a year and it is still 3/4 of the way full. Botanicare actually used to send out very nice sample pack absolutely free, but too many were ending up on ebay for sale so they stopped. They still do samples, but you have to pay. I think it is $16 for four 8oz bottles, but you can pick what you want. That might not be a bad idea actually. You can pick up like one bottle of veg, two bottles of bloom (you use way more bloom nutes) and a bottle of cal mag or something. That's plenty to last someone just getting started quite some time.