How do they attach?
These are wall mounted units. The holes in the top let you attach them with screws, nails, brackets, one picture in the reviews showed someone used tomato wire… pretty much whatever you decide to use.
How many lumens?
I noticed other solar light brands using 182 LED’s having 1000 or 1200 lumens. Judging by the array of LED in this light it’s safe to say it’s at least 1000
They must have used glue when they mounted the light unevenly on that brick house. 
It looks like the bricks are uneven to me…
I’ve had 6 of these off the mothership for a few years now. Overall they work great.
In Florida, they get get enough daily sun for dawn/dusk usage almost year round. Jan/Feb not quite enough sun on a few of them.
They work better than my “smart” floodlight(ring ring) that requires constant TLC.
The only downside: The button for mode changing is on the backside, so once you’re mounted it’s a PITA to change settings. Why would you need to change settings after mounted? If battery runs dry for too long(due to not enough sun) it forgets what it was set to. Not a dealbreaker for me, though.
Overall 4.5/5