Hello Paul,
Thank you for your kind words!
For a garden of around 69 sq/m, a smaller, efficient robot mower would definitely be more cost-effective than artificial grass and can keep your lawn well maintained with minimal effort.
It’s important to note that no robot mower cuts completely right up to the edge; most leave a small strip near borders uncut. Having a neat boarded or slabbed edge helps keep the lawn looking tidy and reduces manual trimming.
There are some fantastic GPS-guided robotic mowers available, but for a lawn your size, they would likely be overkill in terms of cost. A perimeter wire-based model, such as the WORX Landroid M500, would be more than sufficient and more budget-friendly. I have this in my front lawn, and has been working well for several years. There is a slightly smaller model, but this has the blade set in the middle of the mower and doesn't cut to the edge as well as the M500.
Should you want to purchase, link below-
https://uk.worx.com/landroid-m500-plus-robot-mower-up-to-500m2-wr165e/
I hope this helps! Let me know if you’d like more information.
Mark