Loooong post..sorry!
Hi Scrubby! I'm a new member as well, welcome!!!
First off, I'm no expert on rescues by any means, but these opinions are based on my personal experience.
I'd like to share my (recent) adoption experience with you. From start to finish, it took me about 2 weeks to get my dog. I was in constant contact with the rescue and am also guilty of watching my e-mail like a hawk!!!
When you said "interview", I assume you meant a home visit? The home visit is basically so they know what kind of environment their dogs will be going to. They wouldn't exactly want to put a dog that may have been neglected in a home they see as "unfit". They aren't being snobby or anything,

, just looking out for the dogs! Our home visit took about 45 minutes. They asked questions about our existing dogs and wanted to see where they slept, ate, went outside, etc. Our experience was awesome-it was more like sitting down with a friend and talking about the best dog breed ever! (Sorry, I'm biased..

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Reasons they might deny you: if your dogs aren't up-to-date on all of their vaccinations/HW preventatives, etc. If you don't take care of your existing dogs, why would they bestow you with another? I can't really think of any other reasons to be denied..but then again, I'm no expert!!

Someone being turned down because their dog is intact seems odd to me. The rescue I went through spays/neuters all their dogs before they adopt them out. We have two female dogs and adopted a male (most rescues won't do same sex adoptions for dominance reasons) with one of our females being intact. They never said a thing about it. I guess it could differ from rescue to rescue.
I would like to add a BIG thing to be prepared for, which I wasn't expecting, but had to learn to deal with quickly-aggression! Most rescue dogs come from less than perfect homes-my dog for instance, was turned over to the humane society because "he is a fence jumper". I firmly believe that he was left outside alone a lot and maybe tried to escape (if he truly WAS a fence jumper) out of frustration. Boxers are like shadows, everywhere you go, they are there...(even in the bathroom, which is a whole other post!

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I haven't been able to pin-point if he has fear/dominance/jealousy aggression, but he has had some heavy spats with our girls. The good lord willing, that's in the past! (We've gone almost 3 weeks without any squabbling..due to a wonderful dog trainer!!!) I'm not saying EVERY rescue dog will be aggressive, but I went into it thinking everything would be peaches and cream and when the cream started to curdle, I had no idea what to do!
That's my 2 cents. hahaha! But truly, if you do adopt a boxer, you will be in love for the rest of your life.

Best wishes to you and keep us updated! Hope I helped a little..I tend to get excited when I post. LMAO