Excessive Barking & REPotty-Training Help!

I hope I'm in the right forum for this post... if not, someone, let me know!
 
Hi, I have two questions for the dog trainer regarding our dog, Hailey, who is a Miniature Schnauzer who just turned 2. She is on the small side, 11lbs, full of puppy energy, and relishes the center of attention. My husband and I don't have kids (someday, maybe), and while she is spoiled to some extent, we don't treat her like a princess, either. I'm going to go ahead and make this a long message... hopefully, the more information, the better. Hailey is a talker. She loves to bark, gurgle, whine, gargle, grumble, etc. We don't mind her talking, and we often respond to most of her sounds (except barks). We converse with her and she with us... much like a Siamese talks. We do not respond to barking, though, expect with 'no bark' and some other tactics I'll mention in a bit. When she barks, though, it is often quite aggressive. Even such a small dog can make people shy away when her barking is so excited and so aggressive. She has never ever bitten anyone (although she mouths on my husband some when they play).  The problem is that she barks excessively in some situations. For example, when someone comes to the door, we think it is perfectly normal for her to bark... maybe for a minute while people are coming in and she is being acquainted. After that, however, we want her to stop. We'd like to interrupt her, but she'll just keep barking. We've tried 'no bark', placing her outside or in another room, praising her when she takes a breath from barking, ordering her to 'sit', having people pet or pick her up (which sometimes will quiet her)... but nothing really works. She gets in these cycles. She'll occasionally do it with just my husband and I, even if we play with her and try to wear her out.  In the backyard, she'll normally be quiet, but sometimes she gets in the same cycle. We understand that some barking is normal, but after five minutes, we think that she should come inside or quit. If we bring her in, she'll want back out, and we can't get her to quit if she's outside. The same happens on short trips. I'd love to be able to take her with me to garage sales, outdoor events, and short car trips. We've experimented with doing that some, but she just barks at everyone the whole time. Take a garage sale. I'll first ask politely if it's ok that my dog (who is leashed) comes with me as I look around. Almost everyone says 'sure.' I'll bring her up the driveway, looking at tables, etc, as we go. She'll bark for a minute at the garage sale holders, who will talk to her and comment on her cuteness. Then, as each new person comes to the sale, she'll bark, and not just for a minute. She'll bark and bark and bark. I'll try all the things I mentioned earlier. Once in a while, one will work or she'll tire of barking at them. If that happens, and she's quiet, I'll praise her a bunch!  Other times, she'll bark so much that I have to pay and leave because I don't want to be rude and scare off other salers. I'd love to leave her in the car for five minutes (when it's not hot! and with the windows cracked) while I run in to drop off library books, etc, but she'll bark at anything and nothing the WHOLE time. We're reluctant to use a bark collar. We don't mind her 'talking.' We don't want to stop the barking completely or punish her for normal barking... we just want something or some strategy to interrupt the excessive barking cycles. Someone suggested a silent dog whistle, so I bought one, but now I don't know how to use it for that purpose. Would that work? To startle her and get her attention while we try to distract her from barking? Thanks for ANY barking suggestions. Okay, question two. (I know... you'd think I'd be done!) Hailey was extremely difficult to potty train. She was my first dog and my husband's first dog since childhood, and we both work full time. It took us months to train her. We read every book, and the vet was in constant consult. Even the vet agrees: Hailey just doesn't like to go outside. She prefers any place (except our bedroom- which she must view as a den) to outside. We finally got her mostly trained at about 7 months, and she has been slipsliding back and forth between trained and not ever since. Lately, things have been getting worse. We'll let her out after meals, after play, after sleep. We'll walk her out... we'll watch her go. But somehow, she slips past us at random moments and heads to another room to pee or poop. Even if we use baby gates to block off the upstairs and not-currently-being-used-at-that-second rooms, she'll still slip past to an ungated area and find a corner to go. It is incredibly frustrating. We can't lose sight of her for a second. We haven't had any major life changes, but over the past couple of months, it's gotten worse. We've spoken to the vet, and there is no physical problems with her urinary tract or her bowels. In fact, she is an incredibly healthy little dog.  We don't punish her or hit her. She's gotten a tap on the rear here and there (but very seldom, since we know it doesn't really work). We raise our voices in frustration sometimes, but again, we know she doesn't really know why, and it just seems like attention, so we don't do it as often as we feel like it! She's got a crate that she hangs out in during the day while we're at work, but we're reluctant to shut her in it as a punishment, and the vet doesn't recommend doing so. She's been to basic obedience class and passed just fine. She can sit, lay down, stay, and come (although the last two are not perfect.)  If you need more information, just ask. We are in the market for any tips!! Thank you for your time!