It's a lovely piece by one of the designers I really like. However, it's production piece, one that is made in fairly large numbers, and, therefore, unlikely to fetch a large amount, say over 60 pound. It's very unlikely that Edenfalk actually signed the piece. That job was done by soemone near the end of the process.
Most people on this board are extremely reluctant to give a value, because values are very hard to pin down. It all depends on who sees the vase when it's on sale and how much they want it. On eBay it might go for relatively little, say 20 pounds, or it might go for a great deal more if two people want it and start bidding against each other. Even then, I don't see it going for more 100 pounds.
To me, the value in such a piece is very personal and so I would tend not to sell it. But that doesn't help you much.
Good luck at a difficult time.