I forgot about the cat....
I have had good luck introducing dogs and cats and having them get along, but it is an individual thing. If the dog has a high prey drive and hasn't been socialized around smaller animals, it might not work or take significant effort.
I introduce dogs and cats by having the dog on a leash and working the dog on training routines while the cat gets comfortable. Since the cat will likely be a huge dstraction for the dog, I start with just trying to maintain attention on me rather than the cat. High value treats and calm praise to keep the dog focused and as relaxed as possible then just allow the cat the time it needs to come out and see. Wearing the dog out beforehand would be a good idea. The more relaxed the dog is the faster things tend to go and it is important to be mentally relaxed yourself; if you're anxious and excited, the dog and cat will be too.
I don't think I would be able to take her to work with me consistently so her being home alone is one of my biggest concerns, I'm not too concerned about my furniture, more about her happiness and need to go outside.. can they go 8hrs without needing to?
A rule of thumb is that a dog can typically got about 1 hour for each month old they are but more than 8 hours might be asking for trouble. I have had rare incidents where I was away from home longer than expected and my dogs have been exceptionally reliable, but it is unfair to expect them to hold out. If the expectation is 8 hours a day from the start, I would pick the dog up at the beginning of the weekend and if you have any vacation time, it might be a good time to use some so you have as many days as possible to get them used to the new home before you're gone for a long time; it will be a new place to them and they won't know your schedule or what to expect. I would start by giving them some high value treat that they have to work on, like a Kong toy filled with peanut butter which has been in the freezer, then leaving for just a second, out the door and right back. If they keep focused on the treat, I would repeat ging out and in, each time staying out just a bit longer. You want to associate you going out the door as a good thing and establish that you'll be back. Keep repeating it over and over, constantly increasing the time. If you reach a point where the dog seems upset/anticipating your departure, reduce the time you are gone to a point where they aren't upset and start working slowly to increase it through repetition.
8 hours for an 8 month old might be asking too much, especially right from the start. I would check with family and friends, see if someone can stop by and take them out in the middle of the day or perhaps see if there's a dog walking service in the area.
as far as the other issue I do wonder if she could be trained to use a litter box, I'm not desperate to get her but I do think it would be good for me, kind of as a way to force myself to go out more and get some exercise
It is in the realm of possible, but unless you have significant skill and experience in behavior shaping, very unlikely to go well.
sounds like the move is to wait then, I had a feeling that was going to be the answer but figured I'd get some input before I turned the offer down
thank you
At least now you have a better idea and can prepare for a time when you can take care of a canine.