For the front. Just go with newer regular windows. No bow.
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Can you just repaint the siding? What material is it? Do you not like it??
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I’d spend the money on extending the front porch. And upgrading the entryway.
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for the back, the upper portion id just do windows around. The lower level I’d do doors. Any style can really work.
Sliding

French

The ones that are retractable and open all the way up...

I like the color of the house now. I also like the bow window, and if it needs replacing, I would consider another one. It adds curb appeal to the front of the house. The placement of the front windows is just what it should be for that style house. I think the front entry looks good for the style of the house too.

I would replace the windows with like windows. "Interesting widow arrangements"??? Windows are arranged to let light into the home. If you really don't like the bay window you could do a flat picture window or a bow window. I would remove that awning thing over the front door. I don't find it attractive. Replace the garage doors with ones that have a row of windows, no grilles. As fa as the back lower level it looks DIY. Maybe get a professional to give you some advice on those windows

Flat picture window

Looks like the current windows are replacement windows because of the size of the frames. You could do a more traditional window, called a Chicago window to replace the bow. (Bow windows are not ones I personally like.)

A Chicago window, one with a fixed pane center and two outer windows with operable sashes, is see in the lower right on this house. If you are replacing the other windows, I like the style of grids only on the top part of the window like this house has.

Exterior · More Info

Also, I would open up the ceiling of the portico. Right now it looks squat.

PORTICO IDEAS · More Info