As long as the parlor and tattoo artist use a new, clean needle and everything is sanitary, the likelihood of infection is very low.
Your potential tattoo sounds quite large and it might have to be done in several sessions. It’ll also be fairly expensive and something you’ll have to live with for a long time.
Make sure it’s something you really want and don’t be afraid to talk to an artist beforehand to get a feel for the process.

i’d get it behind my ear or on the back of my neck. it’s pretty simple, which is a good thing. if you want to change it to something else later on, it won’t be that hard.