The idea of a trailer has been going through my mind
and am wondering what sort, as in single rear wheel,
or twin wheeled type.

I have one of each, a Bykaboose and a BOB. The single-wheel BOB is
lighter, sturdier, tracks better, seems to have less drag, and is more
stable; the two-wheel Bykaboose is cheaper, holds more, and it folds
flat. Both provide two advantages over racks and panniers [of which I
have plenty]: you can carry more, and the bike is more stable carrying
the load. Racks and panniers are lighter in weight, though, and cheaper;
anyone who do not need to carry a lot of weight and volume of cargo may
be better off with them than with a trailer.

--
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