First it's not SD as pointed out so if it not you could hand up with a pretty large animal.
If you jump from no experience to a 10 feet retic that may not have been worked with on a regular basis, the prey item might be the least of your issues.
My advice if you want to get into retics get an hatchling and get it from a reputable breeder, a 10 feet female craigslist reject (that's already no as advertised) is not the best idea for a new owner to start with no matter are good the deal is.