I bought a 22 year old flat (maisonette) 6 months ago (top floor) and have noticed a crack all around the front door, on the inside. There are no cracks on the outside. I came over to see the flat about 4 times before the sale was completed and no one has noticed the crack which I guess they cleverly hidden for the sale. In the beginning, everyone said there's nothing to worry about as it's just something simple to fix, but I've done nothing about it yet and noticed the crack got much bigger and what scared me the most was that I spent 5 days away for Xmas and when I got back I had to force the door open to get in... Can anyone tell just by looking at the pic if it's something quite simple to fix. And how much it'd cost if I got a professional to come around and fix it. It's just so I have an idea and know he's not overcharging me. Thanks