Haven't got time to read the remaining 35 posts in this thread, so I'll just say "+1"
We have used a push mower for years -- our back lawn is only 10m x 8m. We have bought Qualcast 38cm mowers (we've had two in 20 years). They are light, and they work; my wife actually likes doing the lawn with ours. I wouldn't go for the 30cm job unless your lawn is really tiny.
I too would ask: *why* is there no electric point available? You're doing a favour for the other residents and/or the Lease Owner.
John