You could not do a lot to be honest.
As you entered the premises, you were sort of in defensive mode, after about 15 minutes you tended to know if it was sortable, you couldnt get involved moving furniture, ripping floors up, as the time was not feasible to put it all back again.
With Dual boards if say one rcd wouldnt reset you might just move one usefull circuit, to another spare way just for some power, or possibly bunch up a circuit, maybe make up a lead or two for freezer or table lights.
The people brought the insurance, not reading the small print that it was limited to one hours labour, of course they could have longer if they agreed to pay the insurers, but there rates were ridiculous.
when you told the clients , they werent to pleased, it was all a gimmick and on national tv ads, but I think its all stopped now apart from Direct Line.
Most of our works reactive and constant pressure to, get stores etc back on and minimise stock and trade loss, so you tend to have a back up plan ready.
In the OPs case he called the bloke in so luckily the only restraints was how much the op wanted to pay him direct
A lot of our calls were on sundays, where people had done, diy badly.
One cheeky sod had blown the lights, after about 20 minutes I noted a B+Q box on the bed, despite him being asked on arival if he had any idea what caused it, he then admitted he blew the circuit putting it up, he had then put the old light back hoping we wouldnt notice, on inspection hed joint all the blacks.
he then produced more lights and asked me to put them up at the insurance companies cost, I pointed out the 1 hour time limit and his response was just do what you can till the times up, maybe if hed been honest at the start, i might have.