Question
What is the difference between top soil and garden soil? Which soil would be better for our flower beds?  Should we ask the supplier what is in the garden soil to make it worth more?

Answer
Hi Kevin, In nature, top soil is on top, garden soil is under it.  
If you're buying it, the definition isn't as clear. It will depend on what the seller is blending.  Usually, top soil is leaf compost, finely ground pine bark and sand.  Garden soil is the same, but some amount of clay is added. To blend clay with top soil, it has to be dry and then screened, so there is extra labor involved.  
For your beds, garden soil would be a better choice.  Clay is good for water and nutrient retention.  Jim