Proud new pod parents

Welcome

Welcome.  What you'll need to purchase depends on a lot of things.  First and foremost, what did your dealer include?  I believe all dealers include a battery and propane tank (hopefully full).  Some give you a "starter kit," which includes things like a sewer hose, fresh water hose, water pressure regulator, RV TP, etc.  Ours did not.  If yours didn't either, you will want to pick those things up for sure.  Those are necessary. 

There are lots of other things you may or may not want to purchase.  For instance, you will likely want to have something to level from side to side.  Options include simple 2x4 scraps, Lynx blocks, Anderson leveler, and BAL leveler.  Google for more info.  Many people have surge protectors.  There are tons of things you can do to personalize your R-pod, too, such as adding shelves, interior decor items, etc.

I would suggest that beyond the necessities you may already have (the previously-mentioned hoses and water pressure regulator), go camping somewhere for a couple of nights.  Take a notebook and start noting things you'd like.  Frequent forums like this for additional suggestions and advice.  Consider joining also the R-pod owners Facebook page.  Ask questions.  Enjoy!