I thought about a light, flatbed trailer with a single axle, but I convinced myself to get a tandem axle enclosed trailer. It's safe to park at a hotel overnight, there's redundancy in the second axle with regards to a blowout (4 tires instead of 2), weathering of the car (hail damage, rain), and the list goes on and on.
I paid just over $3000 for my trailer. It's absolutely perfect for the Se7en, and it helped me move out of my house too!