1 For those that want to tape the drywall themselves, plan on paying around $0.10 to $0.32 per square foot to complete the job. 2  A pack of drywall tape can cost anywhere from $4 to $10. 3  For example, the 3M 385 Scotch Drywall Fiberglass Tape retails for $10 to $13. This price is not going to include the paint or primer. 2  According to the price mentioned above, a 500 square foot room can cost anywhere from $175 to $400 to tape and finish the drywall process.