Like any dimmer switch, ensure that your smart switch is compatible with the lights you have installed -- especially if they're LED lights. Lutron, for example, has a compatibility tool you can use to find out which light bulbs (including recessed and can lights) are compatible with their switches.
And, this is an unlikely scenario, but if you are planning on installing smart light switches for sockets that have smart bulbs (like Philips Hue or LIFX) installed in them, you'll have to swap them out for "dumb" bulbs.
Consider your three-way switches
If you have three-way switches (as many of us do in hallways and large rooms, like living rooms) consider how you'll tackle these. At the Xfinity CNET Smart Home, we used Lutron Caseta remotes to make the installation dead-simple, since they look and act like three-way switches, but don't require as much handiwork to pull off.
Cost
That brings me to the next point, and it's a big one: cost. Smart switches are not cheap, especially if you plan to install them throughout your entire home.
Dumb light switches cost just a couple bucks a piece. Installing all new switches in my home would cost roughly $60 (£43 or AU$79). That's just a few dollars more than the cost of one Lutron Caseta Wireless Light Switch, which retails for around $55 (£39 or AU$72). Installing them around my house would cost approximately $1,100 (£787 or AU$1,446).
Given this, you can likely install a few smart bulbs and plugs around the house for a lot less money. But the installation won't be nearly as seamless.
To be fair, not every light in your home needs to be connected. And some switches are redundant, so you wouldn't want to install two smart switches for one set of lights. But the difference in cost is still considerable.
