I got my basenji from a rescue place in Iowa about 2 years ago. In my situation, I had never spent time with a basenji before ( I still have only seen one other than mine once, and it was like for an hour 
). We went with a basenji for the stereotypical reasons (quiet, hypoallergenic, etc) and while there were a lot issues we had to learn how to deal with, overall she fit in with us quite well and we love her more than anything
To help with some of your questions…8-10 hours is fine to be crated while gone, provided you are dedicated to spending time with the dog when you are available. Tosca is in her crate from about 7-4:30 every work day, and does just fine with this. We do not have a fenced in yard, and really the only exercise she gets is an hour and a half walk approximately 4 times a week (sometimes less). In the summer she'll get a bit more exercise, as we will take her to the fenced in baseball field and let her run. In the winter she will occasionally go a whole week with only short walks when the weather is bad. However, when we are home with her, she does get constant attention from one of us. She is often laying by me, or playing with my husband. We also do try to rile her up by playing/wrestling with her in the house as well, but it can be hard to get her to engage in play at times, she just isn't really all that interested in it. She also sleeps with us, so she is not crated at night. When she does play independently its never with regular toys (She has them, but ignores them), it has to be something food related like a rawhide or stuffed kong, so we let her do that occasionally but not all that often, as she will gain too much weight
That all being said, she does really well, but is far from perfect. She does have her moments where she gets bored and will act out (like right now, I am ignoring her so she is running around the living room getting into whatever she can) but usually she is very mellow, and just sits around. She can never be left alone in a room unsupervised, so that can be challenging at times, always having to keep an eye on her. If she is unsupervised she can and will eat things she shouldn't, so its super important to watch her always, which can get annoying. But, all things considering, she is a basenji, and they are very mischevious creatures, so she does pretty well. She is very quiet, which is nice, we do not have to deal with the loud screaming sounds they can make, she only occasionally yodels for food, otherwise is silent
I think as long as you are willing to give your dog lots of attention when you are available, and don't mind having a dog you must CONSTANTLY supervise, things would be fine for you. However, I would say a basenji is not a "typical" dog, they are definitely more challenging, and need lots of attention, you can't just forget about them and let them on their own.
If I had to make a list of pros and cons I would say:
Pros: Clean (never needs bathing/grooming), no doggie smell, very little shedding, quiet, sweet temperment, cuddly, great with kids, learns commands easily (for incentives:) ), nice size, bonds super closely with us
Cons: Runs away ( you gotta be careful even opening the door, they will bolt), needs to be constantly supervised, will eat non edibles which can be dangerous, is not good with other dogs (this is just mine, others can be fine), high energy and destructive at times, house needs to be kept EXTREMELY picked up or problems will occur, can't be left alone
As for expenses, I would say if the dog is healthy, minimal. I spend maybe a couple hundred a year on vet bills (including heartguard/tick meds), like 10-20 a month on food (Granted I do cheaper food than most around here), and minimal for toys/treats. Start up costs might be a little bit more, but you can go cheap if you get a used crate, cheaper toys, and collars/jacket if you need it can be cheap if you just get the basic kinds. Overall I would guess between 300-400 AT MOST a year we spend, however we have (knock on wood) never had any major health problems, that could change things drastically.
If you know you want an older dog, I would recommend taking your time and finding one that fits your lifestyle. Tosca works great for us because she is not a puppy so is pretty mellow (hence not needing as much exercise), she is quiet (some are not), and she is crate trained (again, some are not and can have very severe separation anxiety...not good most likely in your situation). I would just look for a basenji that is the right fit for you, I know in some ways Tosca is a typical basenji, but not in others, each one has different stregnths/weaknesses and you just gotta find the one that would work for you...good luck! I hope this helps, I certainly rambled on enough!
