Hi Photoboy welcome
A+B- I would like to say I was in your position 8 months ago. I live in a block of three houses (converted barn and farm house) We live along side a quiet country road, apart from our group of houses the nearest houses are a 1/2 kilometre away. We the occupants of the three houses all work and are away in the day.
If "electric fencing is a no no" (which i must add is only good if you local fox population have not worked out they can jump it) then you either have to put up a run or be content with loosing you chickens on a regular basis. I started out like you with want to let the girls roam free. After 2 months I lost three chucks out of 8. I then kept them behind an eletric fence 75m of it. This worked till the 28th of Dec when I lost another two chucks and then again last Sunday I lost 5 chucks. You may not see your fox but he/she is there. These chickens where all taken in the day and at the weekend and we where home!!!!! So in the last 8months I have lost 11 chickens to fox. I am now building a run. I have had to give my remaining chicken away till I get my run built.
A+B - I never leave my chucks out (or did) when I was not around or in the house. They will not fly away (b*gger off) as there coop is there home and they feel secure there they know where it is and will go back. When I was out and about and the chickens where loose I would often find them 150m+ down the field. They did come back.
C - A sturdy chicken coop. I am not surprised Sally has mentioned an eglu.
They are good if you can afford one and they do eradicate the problem of red spider mite.
Sally has a good point about your and your neighbours gardens. They will have everything new shoots the lot. You will have upset neighbours. As they will be in those flower beds.
But I love chickens they are fun to watch and give me something to do rather than sat in from of a TV or Computer all night or day.
To summarise: Get chickens you will love them. But I would suggest you get a run for them and let them out when you are outside. Once trained (yes trained) chickens will come to a call and you can put them away.