Some closing thoughts
Using this building technique and materials in something approximately 7-8" in diameter and 6' tall, you have a practical minimum weight limit, assuming a 48" chute, altimeter, kevlar, nomex, 29mm stuffer tube, glue, motor retainer, eye bolts, pml upper tube, and some ply upper and lower centering rings that would be common to any design of around 32-40 ounces for the core components. Add to that your foam outer skin and structure, and lightweight carbon re-inforced fins and you have a practical minimum dry weight of 50-55 ounces. Motor weight can run from 4.5-13 ounces for G-80 to I-200 motors and assuming you need no additional nose weight. You may be able to cut an ounce here and there by using cardboard upper tubing, instead of PML phenolic, but the phenolic helps in giving a naturally nose heavy design.
This is nice for rockets that do not have large fins and normally need lots of nose weight(aka hellfire missile), or for something that is in impressive scale, but does not require an expensive motor, or a large field to fly in.
Of course you can scale this down as well, I've done a 5.5" by 48" tall Pershing 1A that is 20 ounces ready to fly using motor ejection and a very thin 36"chute and can use 24mm motors.
You could also consider using foam board(from dollar tree) as a cheaper but slightly heavier structural component and some sort of cardboard/cardstock material for the skin, but which would require some waterproofing/paint or covering material.