There are plenty of easy to use and inexpensive products that will produce just as good of results as any of the expensive stuff out there. There are plenty of people using DynaGrow without any additives getting better results than the chemists with their eye droppers mixing up some ridiculous potion from ten to twenty bottles of overpriced, over hyped, and aggressively marketed bottles of 99% water. I like a three part product called VitaGrow and it is the cheapest out there and will give you more control and as good or better results.
It's basically:
Part A: Micronutrients 4-14-24
Part B: Calcium Nitrate 17-0-0
Part C: Monopotassium Phosphate 0-51-34
You use part A and part B for grow
You add part C for Bloom
Done
It's just repackaged calcium nitrate, monopotassium phosphate, and a basic micronutient mix. If you want a P/K boost add more part C. Faster growth in veg add a little more part B. Everything any plant needs to grow is in this mix. You can adjust it according to specific plant requirements just by changing the amounts of each part.
You can buy all the ingredients yourself but the markup VitaGrow charges is minimal and you can buy as little as a 1 pound box of each part. Get a box of Epsom salt "magnesium sulphate" for a couple bucks at any grocery or drug store and you have everything you need.