OK expensive is a relative term. Think invisible dog fence boundary wire install. They go around the perimeter of the property, and around every object you don't want to mow like flower beds, trees, etc. Then, depending on the model purchased, you install one or more "return wires" - that is the path the mower takes to get from far away point A to far away point B. If you want, a mower can cross a path or even a driveway but that is not recommended as people can and have backed over a mower transiting a driveway before. Ask my landscaper, his sister in law ran theirs over not even a month after he installed it for them. He tried talking them into the more expensive model (the one I bought) that could go around the house to the opposite side of the driveway, but no dice, they were cheap and guess what, it's not covered under warranty if your SUV pancakes it
Anyways. Multiple models available, depends on the size and hill slope of your house what one to get. I had to reconfigure my ditch lines because they were too steep and the mower would get trapped if it rained. Landscaper and I talked about it before installation and he thought there was a 50/50 chance it'd work "as is". We decided to give it a shot and worst case scenario we'd reconfigure the ditches for an agreed on price of $300 going into it so no big surprises. Well, we had a super super wet spring and the ditch gets just enough water in it to turn it to mud with a mower going over it and scrabbling for purchase on wet grass to climb the other side. So, once it dried up, we (aka he) dug the ditch down a foot, installed a couple tons of river rock and a drainage tile to the property edge, and then backfilled with a couple tons of black dirt, and sodded over the top. 4 weeks later, Snippy the mower was allowed back into the area and bam, it is perfect and even with a 5.82" rain in 8 hours we got a couple weeks ago (yes, I measured, and yes, that's a TON of rain) the ditch was wet for maybe an hour and it drained away and worked perfect.
Long story short, Snippy the mower is working away 24/7 and in the dead heat of summer I shut it off to dusk to dawn operation to prevent the yard from burning. It's set on the highest of 10 height adjustment settings.
My landscaper lives on a nice golf course. He put his first one in at home and put signs up because it was constant questions with a flyer box like a real estate office puts in front of houses. For a professional landscaper to do that - where mowing contracts are life - is pretty gutsy.

He said he sold a dozen the first month just from that and word of mouth is the best salesperson. He's the largest dealer in our area. Last year he sold about 70 he said. By the end of May this year he had sold over 100 and last time I talked to him they were doing 2 installs a day, he goes to home shows and advertises them that way.
All in I was at $3387.53 including the ditch reconfiguration. Mower was $2495.
Here's the app pictures. Note - Snippy does not mow in a traditional fashion, think of it like an etch-a-sketch, it senses the length of grass, and how many passes it takes to completely cut the area. It takes about 5 weeks to map out your yard, by learning the boundary area wires, and using GPS. It then determines areas that grow faster, like over a septic field and knows to mow them more frequently.
Sounds like witchcraft I know. But it works.
It can mow more, or less, based on it's weather sensor too.
Height can be adjusted from a nice normal "looks like you mowed a couple days ago" length, down to golf green height. But it cannot adjust the height in different areas - wish it could do that.
It runs about an hour per charge, takes about an hour to charge as well. Not that you worry about it since it is always on...
Blades are dirt cheap, they look like disposable extension knife blades, super thin and sharp. Change about every month you can tell you need them changed when you can hear the mower cutting the grass because the blade is dull and it is audible cutting through the grass vs. snicking through it like a hot knife through butter making virtually no sound. Pack of 30 on Amazon for generics is $16 and yes they are identical to the Husqvarna product.
10/10 would buy again.
Husqvarna Automower 403X Home Page
Landscaper's facebook page -
https://www.facebook.com/langtongroup/vi...39/?type=2&theater