Hundreds of people turned out to see the 29-year-old twins and the show's host Scott Cam at the Mitre 10 store in Hume, speaking from the back of a truck in one of the back sheds.

The twins and four couples renovated a South Melbourne hotel block, transforming them into five luxury apartments which go to auction on Saturday, the finale shown on WIN on Sunday. Each of the 220-square-metre apartments has three bedrooms and five bathrooms and comes fully furnished.

The twins have the first-floor apartment but their style and the extra money they won throughout the competition has led some to suggest theirs is ''the real penthouse''.

Each couple will keep the profit from the auction of their own property. And after the last auctioneer's hammer goes down, the couple whose property makes the most over reserve wins an extra $100,000.

''I've just got this anxiety inside me that I can't get rid of,'' Lysandra said.

''I think what's making Alisa and I nervous is all these write-ups about us being the favourites and I feel it puts a little bit of pressure on us.''

Alisa said reports about a development being built next to The Block apartments which might have some impact on views was also troubling them.

''That's starting to play on our minds more than it had the whole competition because we really didn't give it any consideration and now it's been brought into the media, you do start to doubt that and whether people want your apartment because of that development,'' she said.

The twins, who want to start their own interior design business, have put Sydneysiders Madi and Jarrod on level four as the real favourites, rather than Trixie and Johnno from Brisbane, who have the penthouse.

''I think Trixie and Johnno's is very individual whereas Madi and Jarrod's is probably more mainstream and they still have the views,'' Alisa said.

The girls said they would "just leave things to fate''.

Their Canberra fans were in no doubt the twins were on a winner, laughing along to their wisecracks with Cam, with many in the crowd children who seemed just as entranced by the renovations.

ACT Chamber of Commerce chief executive officer Andrew Blyth was there with his six-year-old twins Ava and Elisabeth.

''They are right into it,'' Mr Blyth said. ''They'll walk around the house and say, 'This is the bedroom' and 'This what we've done with the laundry'.''

Belinda Gasperksi, of Holt, said her six-year-old daughter Laura knew the whole show and its contestants ''off by heart''.

''She likes Lysandra. She used to call her Lasagne,'' she said.

The twins said their $48,000 in winnings along the way didn't endear them to their fellow contestants.

''By the end of it, nobody was talking to us,'' Alisa said.

The twins also revealed a soft spot for The Block's gruff foreman Keith.

"See, we like Scotty but we love Keith,'' Alisa said, adding he followed their own philosophy of treating people the way they wanted to be treated.

They also got a little teary talking about leaving their young families at home but said they were the reason they were doing The Block, even if it never seemed to end.

"It's certainly been a ride and it does feel like we've been doing it for a while but it's coming to an end and we've enjoyed so much of it, but it hasn't been easy,'' Lysandra said.

There are definitely big bucks up for grabs for all that hard slog.

Earlier this year Phil and Amity from Adelaide won The Block All Stars, taking home $375,000, while in 2012 Brad and Lara walked away with $606,000.

Across seven series, The Block has distributed more than $4.3 million in prize money to contestants.

Cam said he didn't know the auction reserves until he announced them to the contestants.

"It's hard to say [how the auctions will go],'' he said. "Our show is a true reality show and the buyer determines our winner so it's really up to real estate market. We have no idea.''

And while he refused to be drawn on favourites ("I love all the apartments equally, like my children – and the contestants''), he did say he enjoyed being with the twins.

"I think they're great workers and they've done a fantastic job on their apartment. They're real goers and I like them for that,'' he said.

And the crowd wanted to know when The Block was going to do over a property in Canberra.

''Funny you say that...'' Cam teased. ''Well, we're not bringing The Block to Canberra but we may well come to Canberra one day. That big white house? The old one? How about we do that one up?''

Old Parliament House seems safe from room reveals and bedhead challenges, at least for now.