Outrageously expensive quote?

So! I'm currently in Aus, where I've just managed to sell my house, and I'm heading back to NZ to take care of my Mum, who's having some health issues. I'll have to move back into my old 32 square meter unit, but I've gotten pretty used to living in a nice, big place, so I figure! If I'm going to live in 32 square meters, I want to make it the best 32 square meters I can! So I contact a builder with my plans...

The extension would add an extra 4 square meters, and I thought would be fairly simple as the roof already extends out over that part of the deck. I'd also want some new tiles in the kitchen and bathroom and vinyl wooden flooring throughout the house. Get a new toilet, shower, sink and a new small kitchen.

It's a bit of work, but it's a small space, so to my layman mind I thought it'd cost 50k max. I got a quote today saying it'd cost, MINIMUM, 220k - 250k... Isn't that an around 30% deposit on a house? Not a renovation quote for a small unit? Are they trying to scam me, or is this the state of NZ builders right now?

Might have to go the DIY route...

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