I have two litter mater 5 month old bitches, and yes they have been very hard work, initially we had a puppy pen set up in the lounge with a large dog cage bedroom.
Then we progressed to putting them into seperate cages next to each other (doors open)so that they can sleep seperately if they wish, in the utility room with a lino'ed area and dog flap.
Externally we limited them to a flagged area , except when we are around then they get the run of the garden.
I tried the seperate walking, but eventually found it a slog and now do take them out together, it is working at the moment, as they mature they have different personalities , one is laid back , the other is more manic, but they are both devoted to me , but affectionate/loving with each other .I am not worried regarding their training .I have never specifically trained my Cockers , they have evolved with me and my life style and other than lacking strong social skills (due to the fact we live in a fairly remote area) I have never had any problems with them .
I was told they would not pick up their names, would be difficult to toilet train, would not bond to me !! they learned their seperate names within a week , therefore are totally aware when instruction is put their way...once they were allowed constant access to the back door, their habits improved overnight (literally) and yes when it rains we have had one or two 'accidents',... and the bonding is as stong as it could be
OK I know there are times ahead when they mature ,when things MAY change, I cannot see into the future just take things as they come .