Post an inspiration picture.

Costs vary by location so you're not going to find much information on that here.

Blending in with the neighborhood also varies. There was an uproar in a neighborhood near me this past summer when an ultra-modern home taller than all the others on the street was built among New England capes and ranches.

You have a garage with a house attached to it.

The most prominent features of this Dutch Colonial detailed, contemporary split level are the garage doors and the BLACK roof.

I'd figure out how to address the doors first and go from there. There's not much you can do to this composition.

I personally would focus on the garage doors and siding to make a radical difference for a scandi style. Get a quote for new garage doors for a starter and go from there.

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Take off the shutters; mahogany garage doors, use the colors of the stone for the body of the house.

Tagging onto Beverly's comment, I would try to mask the prominence of the garage with some natural features. Perhaps you can add a pergola over the garage doors and lattice on the sides to allow for climbing vines to soften that big block of garage. (Pay attention to the idea of the climining vines/flowers, not necessarily the style of the homes they are on.) Some inspo:

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To give your home a more modern look I would simply replace the garage doors with glass panel ones with black frames, remove the shutters, paint the window frames black to match the garage doors, and install large black modern sconces.

Some option

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