Many homeowners have good intentions when they start a home improvement project. They want to save money, for sure; and there’s a lot of satisfaction to be had when doing it yourself.

There are occasions, though, when even a DIYer with better-than-average know-how is overmatched. If you’re looking around the house at an extensive honey-do list, here are four projects that you may consider doing yourself, but should probably hire a professional.

Refinishing hardwood floors

This is not a job that you want to do by hand or with a handheld or belt sander. Yes, you can rent a floor sander and buy everything you need, but if the equipment is not calibrated correctly, or if you make a mistake, it could cost you MORE to have a pro come in to fix the damage that you did. Floors that are not properly finished are easy to spot. Hardwood floors are very desirable these days, and can increase the resale value of your home.

Installing a water heater

Whether you’re installing a traditional water heater, or a tankless system, most municipalities require a building permit to complete the job. A traditional tank heater requires water and gas connections, which means hiring a licensed plumber. A tankless system has the added challenge of an electrical connection. The advantage of a tankless water heater is that it heats water as you use it, instead of heating and storing the water, which means that your hot-water supply is essentially endless. There’s no bulky tank taking up a corner of the basement; there’s no pilot light, so it’s safer; and it will very likely lower your utility bills. Oh, and you’ll never run out of hot water because a tankless system will heat 180 gallons of water per hour.

Installing a lamppost

Any time you have to add new wiring, the project is best left to a professional electrician. They will know and adhere to building codes, which makes it easier to pass inspection. This is a very involved project, requiring drilling a hole in your home to run new wiring, digging a trench for the cable, pouring a concrete base and running the cable through the base.

Sheetrocking

This is one of those jobs that seems very easy, but requires a high level of workmanship. Not only does it require more than one able-bodied person to put the sheetrock in place, mudding is involved, usually more than one application. Drywall compound dries very quickly and requires sanding, which kicks up dust. A professional gets it done quickly without the mess, which means it’s ready to paint more quickly (a job you can definitely do yourself.)

There are plenty of projects to keep DIYers busy around the house. These are just four projects that are best left to the pros. What did we miss? What projects have you started only to realize that you should hire a professional?