Be selective with these cameras. Condition is key. Bad bellows will be extremely costly to repair (read new bellows, made in the UK by special order - ask me how I know).
Shutters may be in bad shape.
I'd rather hold out for coated lenses (Red T*) and shutters with flash synch for versatility (Compur Rapid or Synchro Compur).
Albada finders tend to yellow with age and their framelines may desilver.
Having said that, I did have some very nice results with one with an uncoated lens that someone was kind enough to lend me for 1 month. Another one with uncoated lens that I bought was horrible, so it is a toss up.
On the plus side, these are very tiny, pocketable cameras.
On the down side, the red window winding is a bit tedious, and I get anxious about having to finish 16 frames. I know that sounds funny when you have 36 frames with 35mm film, but that's how it feels.
For about the same money, I'd rather have a nice Super Ikonta B, BX, III, IV, or an Agfa Super Isolette (OK, some of these may be more money). These all shoot 6x6, and have automated frame spacing.
In answer to your other questions, a properly aligned and serviced Super Ikonta will accurately focus to its minimum focus distance wide open with the rangefinder. It is a Zeiss product, after all.