Not all researchers agree on the percentage of ROI each update will get you, but they all (generally) agree on the which improvements are at the top.
UPGRADE ROI
Refinished Hardwood Floors 147%
New Hardwood Floors 118%
Garage Door Replacement 94% - 103%
Replace siding with stone veneer 92% - 102%
Replace Front Door 64% - 101%
Minor Kitchen Remodel 71% - 99%
Siding Replacement 69% - 72%
Window Replacement 67% - 90%
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