Buying a phone at Target

[CalDisneyMomof2]

Can you use Target Gift cards to pay for a phone at Target? I have hundreds that I was going to use for Disney gift cards but need a phone now. (I'm going to buy the gift cards at Sam's now anyway)

Also, anyone know if Target taxes on the discounted price or the full retail price? When I've bought at Verizon they tax you on the $600 value rather than how Sam's Club or Costco tax you just on the $200 that you're charged.