Inviting Bees to Live in My Garden

Well having learned a bit about bees, the next thing is to try and encourage them to visit and to make their homes in my garden. Since attending the Natural Beekeeping course at the beginnning of April, I have sown a few packets of bee/butterfly friendly flower seeds, in the hope that my ducks won't eat them all, and that a few plants will survive and grow to flower. I have also placed some bumble bee and solitary bee nest boxes around the garden in the hope of attracting different varieties of wild bees to nest. My garden is still very much a work in progress, with the new pond taking up a large protion of it, and the new fruit trees planted in the early spring not yet producing blossom (after my gardner cut down my apple trees last year! Not hiring that gardner again!). I have a few flowers in the garden, but its certainly not the year round blanket of colour, buzzing with bees and butterflies, that I would like it to be. I am currently in the process of buying an extra plot of land adjoining my garden - just a small piece 6 metres by 5 metres, which will be ideal for a couple of beehives for honey bees, once I've cleared the rubish out and planted a few flowers.
The next thing is how to get the honeybees to live there. I have a topbar hive on order which I expect to arrive in the next few days, which will make a nice naturalistic home for a colony of bees. But where to get the bees? The ideal would be to find a swarm, or to attract one to my garden, which can then be encouraged to live in the hive. To that end I have placed a bait hive (a Skep baited with lemongrass oil as a lure) on top of my conservatory roof. The idea is that scout bees from any swarms in the vicinity will be attracted by the smell, and check out the skep, then finding that it meets the requirements for a new home, go back to the swarm and tell the others, who will then come in mass and move into the Skep. It is then simply a matter of transferring them from the skep to the top bar hive.
I'm not too hopeful that it will work though. Firstly its probably too late in the season now, secondly I don't know if there are any honeybee colonies in the immediate vicinity that would be likely to cast off a swarm. Judging by how few honeybees I've seen in my garden, I think it unlikely. Thirdly, there still haven't been any takers for the bumble bee houses that I put in the garden earlier in the year, despite the fact that I've seen loads of bumble bees in the garden, including queens who appeared to be looking for nest sites. Oh well, maybe the bumble bees houses will be occupied next year. Regarding the honey bees, I may have to resort to buying some.
Bees bought from commercial beekeepers generally are bought as "Nucs" - nucleus colonies, consisting of 5 or 6 frames with artificial foundation, on which the bees have built cells for brood and stores. They come with a queen and a good number of workers. The frames will fit into the brood box of a National Hive or WBC Hive, but will not fit into a Topbar Hive. Although there are ways of adapting Nucs to fit into a Tobbar Hive, it is messy, and can result in the loss of brood. Either a "Shook Swarm" can be created, by transferrring the Queen and worker bees into the Topbar hive, but leaving the brood, so that the bees will act like a new swarm, and start building comb in the new hive. Some of the foundation containing honey and pollen can be cut down to size and put in to the Topbar hive to feed them, as they will not have tummys full of honey as swarming bees do in preparation. This means however, effectively killing all the brood from the Nuc (or leaving them to die), something which I really don't want to do. One can attempt to remove all the combs from the frames and cut them all down to size to fit into the Topbar Hive, attaching them to the top bars, but this is difficult if the comb is full of brood, and may be impossible to do without destroying brood. Again, not desireable.
Another method is to convert a National Hive or Dadant Hive into a Top bar hive. Phil chandler (the Barefoot Beekeeper) shows how to do this on Youtube. But this means buying or obtaining a National Hive (which is expensive) or at least a couple of brood boxes of a National Hive, in which to put the frames of the Nuc. It is a less destructive method, and the transfer takes place over time.

Bait hive on my conservatory roof.