It's a shed!

Why does Tim Collins want it?
Why would Terese want it, it's hardly Lassiter's style
Paul only seems to want it because Tim Collins and Terese want it.
Leo the slime is the only one with a good idea behind it.

But it's still a shed and from what little they have shown of the outside area, it doesn't look like it is in a prime location and I am sure they showed a couple of scenes were there was junk piles outside. So even if they knock it down and build something else in it's place, it's not a good location.

I am really not sure where they are going with this surrogacy storyline, the only thing I think they are leading to is Toadie pushing away from Sonya just in time for Dee to return. Toadie is annoying me a little, not as much as Sonya who keeps acting without thinking or talking to Toadie, but Toadie is clearly uncomfortable with this, yet he says nothing. As for where Steph and Mark are going, I can't see Sonya getting pregnant and if one of Steph's kids don't return, maybe they come across someone in need of a home (like Toadie did with Callum) and adopt.

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Your failures are your own, old man!