I couldn't agree with tonyb286 more. If there is ANY doubt in your mind, I would definitely wait. Enjoy the good days with Toby and be with him on the bad, and when there aren't any more good days left, which could be soon, you'll know its time.
Hi. It is virtually impossible for anyone here to give you good advice on this ... you are there, you know what the situation is in real terms and you know your dog better than anyone else. I would however say, if there's doubt in your mind, leave it and keep reassessing as time goes on. Your dog's age, the congestive heart failure and other health concerns are certainly major issues - and complicated ones too. The amount of medications are another problem, because there may be interactions between them that will further affect your dog's health. Over time, this volume of medications will likely also cause other issues. But, quality of life is everything, so if there are more good days than bad ... that's very positive. I tend to think this is more a watch and see scenario ... things could change very quickly, so you certainly need to be prepared. Our dogs are often the best judgement of "when the right time has come". They talk to us with their eyes, and when you get "that look", you'll know the time has come.
Different vets may tell you different things, and that's just because like all of us, vets are only human and they have different opinions. You are the best judge of what is the best for your dog - and that means, despite the anguish, you just need to be courageous, when the time comes. I would take this day-by-day and try not to fret about it too much.