Although some projects increase property values more than others, the majority of home improvement projects don’t return 100% of the renovation cost at resale, which is part of the reason why homeowners’ main concern is often cost-efficiency. According to Remodeling Magazine‘s Cost vs. Value report for 2014, wood deck additions, siding replacement, and attic bedrooms are the three most cost-efficient improvements, providing returns on investment of 87.4%, 87%, and 84.3% respectively.

The report also reveals that there are some projects that have particularly poor ROIs. Home office remodels, sun room additions, and master suite additions each provide ROIs of just 48.9%, 51.7%, and 67.5% respectively.

The length of a project is another major concern for homeowners, as many often improve their homes in order to sell them faster. This Old House reports fresh coats of paint, crown molding, and water-efficient dishwashers are some of the fastest, easiest additions homeowners can make to improve their property values.

However, one in five DIY-ers wind up in the hospitals each year as the result of home improvement accidents, according to the Home Safety Council. Although it might not be the most important concern, homeowners should also definitely consider the danger of some home improvement projects before taking them on.

HutchNews.com reports that the seven most dangerous home improvement projects are tree removals, asbestos removals, roof repairs, electrical repairs, gas appliance repairs, knocking walls down, and pest control.

If considering any of these projects, it’s best to leave them to the experts, and when considering any other home improvement project, safety should also be a priority. No one should wind up in the hospital when fixing their homes, after all.