I use Forest drapery rails (https://www.forestgroup.com/). They're awesome, they have a zwave interface build in (the ones I use - they have multiple systems) and they have been 100% rock solid for 4+ years for me. They behave like light dimmers, so you just send them a '50%' message to close them half way etc. Also, you can still open them by hand; if you give them a slight tug, they will open or close the rest by themselves depending on the current positions. Many electric curtain rails, you can't open and close by hand. So if, say, the babysitter tries to close them and she doesn't know that they're electrical, and she starts yanking them, it'll damage the motor. The ones from Forest don't have that.
Furthermore, the company had great service. I wanted these rails when they were just on the market, and I told my installer what I wanted, but he didn't know about the zwave type yet. So I called my local Forest office (in the Netherlands) and they immediately put me through to an engineer who gave me the SKU for the installer to order, and he also gave me excellent advice on how to configure things (in a technical way, not in a 'this is what the manual says' way) and on the different options. They have different types, with different motors, depending on the curtain length. He said 'try the light one first, I think they'll work fine for your length. If they don't work as you want, you can just swap out the motors, it's all compatible. Just tell your installer to return it to <address>, label it <this guys name> and have your installer call me on <guys' cell phone nr> if he has any questions.' That was such a breath of fresh air, being used to companies that jerk you around from one call center lackey to another, reading you prepared scripts with snippets of the manual that you've already read half a dozen times.
Fully second this, we also have Forest. They have proven to be the most reliable Home Automation part in our home.
Prices start at about EUR 500, but increase with curtain length (excluding the curtains). Seems like at lot, but having to recalibrate / repair a cheaper system every now and then will be more expensive in the end when your time is valuable.
I don't quite remember, but e.g. this online shop https://www.hashop.nl/Shuttle has them for e460 = USD533 (includes 21% VAT). But it must depend on the length, and on whether you need special shapes (e.g., I have two bay windows), so YMMV.
Sounds like a lot of money, but out of all automated things, the curtains are the things of which I most often think 'that is very convenient, glad I spend the time and money'. Most other HA things are fun to play with, but not really all that important (in my experience).
