With some hesitation, I think you should give the rescue centre another chance. I don't mean you any disrespect by the 'hesitation' remark, what I'm getting at here is the rescue centres are putting the dog's welfare way (way) above yours and they (I hope) are testing your commitment well beyond mere words.You might think that your impeccable intentions qualify you to adopt, and perhaps they do, but this is not a buyer's market and you should treat it this way.

Its already been mentioned here what the credit checks and means-testing are for; if these people are doing their jobs correctly, they will throw everything possible at you to discourage you from taking on a dog and unless you can persuade them you are the 'right' owner, note that the onus is on YOU to prove that, then you should expect to be unsuccessful.

I've nothing to doubt that you could provide a suitable and caring environment for a Dane but you have to understand that, if the centre is doing its job properly, they will want to be 100% certain of that. Taking on a rescue dog, like Boxer said, means you are taking on a whole lot more than you would if you were buying a new puppy. Again, expect to spend some time convincing a responsible breeder you can provide a suitable home - if they are not bothered then you can bet that it's their dogs that are probably ending up needing re-homing and you should avoid them if at all possible.

Taking on rescue dogs, again as Boxer more-or-less said, is not usually a cheap route to ownership, especially with pedigree breeds for some reasons. Again, I'm not doubting your good intentions but if you're looking to save money owning a Dane then rescue is probably not your best option. Insurance for example, is often cheaper if you can insure with the same company for the life of the dog; it's unlikely you can do this with a rescue animal. You would probably need a pre-insurance examination by an independent vet and any pre-existing conditions would almost certainly be excluded from coverage. Well, that's how it works on the UK at least!

My partner has been approached a good number of times by our regional Weimaraner rescue centre to pre-check homes/owners and you just wouldn't believe the unsuitability of most applicants. It's this track record that, I suspect, you're up against where you live too!