Should I sell my home to a contact or give it to an estate agent?

If it was me, and in this market, I would definitely put it on the market. It's hard to imagine a scenario where you won't at least sell for as much as in a private sale - you can always set the asking as the amount you'd have agreed in private sale plus 5% to cover costs.

The upside is potentially significant if you get more than one bidder. I've seen some houses in south dublin go way over what an EA might have guided.