I need advice about living with my schizophrenic father

My father was diagnosed with schizophrenia when I was maybe 8 or 9. I am 29 now. When I was young, no one explained to me what was happening to my Dad, I was just told he had a “chemical imbalance” in his brain. My mother couldn’t handle what was happening to my father, and so they divorced when I was 13. Even as an adolescent, I felt like everyone was abandoning my Dad. My older sister went to college, and my Mom wanted to take my younger sister and I and move away. I decided to stay with my Dad. Things did not go well when that happened. I was very rebellious, and my Dad didn’t have the capacity to properly parent me. At the time, he was drinking a lot, and he would stop taking his medication. It was a dark time, and I have a lot of issues stemming from it. He was never abusive, though. I would say the worst thing he did was buy my friends and I liquor one time. It only lasted about a year and a half, and then social services took me away, citing neglect. Towards the end, I was suicidal. After all that, I still didn’t want to live with my mother, because she was mildly abusive towards me and we never got along. I was forced to live with her anyway.
Fast forward to the present…I have been married about a year, I have been with my husband for about 7 years. I am diagnosed bi-polar and I take medication for it. I also have severe social anxiety. I have had it my whole life. I see my therapist about once a month. A lot of my young adulthood I spent binge drinking, couch-surfing, and I was even homeless for at least a year. I am an alcoholic, and I still let loose and drink about once a month. My husband supports me. About a year ago I had to have major abdominal surgery, and it turned out the mass was endometriosis. The upshot of all that is, I have chronic pain issues. I live in Colorado, so I also smoke pot occasionally for my pain. Also, I am unable to have children. I don’t take medication for my pain issues besides ibuprofen because I don’t want to get addicted to pain pills. Also, I am unable to have children. I only work part-time online. I am trying to take care of myself. I try to follow a healthy diet, I quit smoking, and I practice yoga. I work on myself, too. I have CBT and DBT workbooks.
My Dad self-destructed after about another year or so, and finally his Mom stepped in and took care of him. He has struggled with schizophrenia through all these years, but we always kept in touch, and saw each other semi-regularly. We had as good of a relationship as could be expected…there were times when he was lost to me. By that I mean, his personality and lucidness were almost non-existent. Things went in cycles, he would do better and then relapse. This whole time he was living with his mother. Then, about 6 years ago, he became physically ill. I haven’t ever gotten a straight story from anyone what happened exactly, but he became physically ill and refused to go to the doctor. Eventually, his sister called an ambulance and forced him to go. While he was in the hospital, he almost died. I was living in New Mexico at the time. Eventually he got better, he quit smoking and had to stay in a nursing home for awhile to rehabilitate. When he was ready to go home, he didn’t want to live with his mother. About my grandmother: I believe she is mentally ill as well, and she isn’t a very good person at all. She’s mean, and controlling, and angry all the time. My Dad said she had a nervous breakdown once when he was little, and had to be hospitalized.
Anyway, everyone agreed that it was in Dad’s best interest to gain independence from my grandmother. So he has been living on his own now for awhile, and he really likes it. He has made friends where he lives, and he was going to a mental health center regularly. He has a cat that he takes care of. He seems like he is doing the best he has in years. The problem is he has run out of money to pay his rent. Apparently, he was relying on his inheritance. He is on disability, but it isn’t enough for him to live on his own. He has courted the idea of living with one of his friends, but he doesn’t want to live in a bad neighborhood in the city he lives in, and that is all he would probably be able to afford. He can’t live with his Mom because her house is full; my cousin and aunt live with her and take care of her.
So he called me yesterday, and asked if he could live with me and my husband, assuming he completely runs out of options. We do have a spare room, and we could use the extra rent money. He has stayed with us earlier in the summer, but the visit didn’t exactly go well. We still have issues. The easiest way I can put it is that I am very sensitive, and sometimes my Dad doesn’t have a social filter. He can be brutally honest. I think it is part of his illness. The long and short of it is that he hurt my feelings the last time he was here. He has his routine: he listens to classical music most of the day, and works on something he calls his “theory.” He believes he is always making new discoveries in theoretical physics. I used to believe it, because he is highly intelligent, but now I suspect it is a grand delusion of his. I have my routine: I take care of the house, work online, work out, play video games, watch T.V. The last time he was here, it was exhausting just trying to do things he liked to do and entertain him because we don’t really like doing the same thing. But I am still having a hard time saying no, especially if he has no other options. I really don’t want him to have to get rid of his cat, because she has helped him immensely. I don’t want him to end up in a halfway home or something similar because I feel like those places are scary and run-down. And honestly, even though there is no room for him, I still don’t think it would be a good idea for him to live with his Mom again. She is smothering, and toxic. On the other hand, his entire support system is in the city he lives in, not here. I live in a very small town about a 4 hour drive from the city he lives in. There is a mental health center in the next town over, but I am worried he would miss his family and friends that all live in the city. I’m worried he would relapse from all the change. My first instinct was to say yes. My husband said yes. I kind of do want him to stay. But I feel uneasy, and guilty for feeling uneasy. I just don’t know what to do. So I need advice: Should I try to help my Dad and let him live here? If I don’t let him live here, how can I help him find a better living situation? If I do let him live here, how can I help him set up a support system he needs? Honestly, how can I say no without seeming callous and uncaring? What steps do I need to take to make the living situation harmonious, assuming I do let him live here?