As a new seller, there is a limit to how much you can list, both in quantity and value. If you go to your Selling page, there should be a box that shows you your selling limits. You can request an increase in your limits once a month.
Many sellers here will also advise that you would be better off starting to do some buying on this account before selling, to get an idea of how eBay works and to build up some feedback. While feedback isn't worth a lot nowadays (it's mainly for PR purposes), listing a $5000 item with 0 feedback is a HUGE target for unscrupulous buyers.
Edit: Also, to give you an idea of how long it might be before your limit is raised high enough to sell a $5000 item: I am a casual seller of used personal media, only selling here and there, and only recently (2 years after starting this account) were my limits raised about $5000. Again, you can ask for an increase once a month, so you might get there sooner, but it's still going to take a while.