Nest accessible?
Set up a nuc or brood box+floor (depending on nest size) next to it. Make frames without wax and fit 3 or so rubber bands to each. Have ready a
large deep tray and sharp knife, buckets with lids and one with water. A red light will allow you to work without disturbing the bees.
Smoke the bees a little. Cut off the combs, trim to fit the frame, slot the comb between the rubber bands, and put the frame into the box. Fit off-cuts into a frame, like pieces of a jigsaw. Work carefully, because you don't know the location of the queen. It will be a sticky job so wash gloves and tools regularly.
Once the combs are framed, scrape all the wax from whatever surfaces the nest was using and add it to a feeder. At this point you could fit the bee-vac to the nuc or brood box (pre-drill a hole) and hoover in the stragglers. I worry when the box has frames in it because the bees shoot straight into a side bar.
Leave the box where the nest was for 24-48 hours to allow the bees to locate to the box (so long as the queen is in it) and then fit a travel screen, seal & strap it and park it in its new home more than three miles away.
If the queen isn't in the box you'll know by the behaviour of the bees, and she will have to be found. This is the point when determination, intuition and poking about leads you to another less accessible roof section, and the sweaty game with a hoover continues.
After all this, the roof must be cleaned of all honey and wax, repairs made to prevent future access to swarms, and the whole area painted or sprayed with a powerful smell to conceal the smell of bee.
A slow, sweaty, sticky and tiring job, I can assure you.
