10yr old neutered male spraying really think it is a behavior issue

Sorry this is so long....I am so sad and frustrated becoming a nervous wreck!My neighborhood became overrun with cats this year and being the bleeding heart I am I ended up with a second male black who is now neutered and comes in and out(who the 10 yr old seems not to like and the female seems afraid of) and an outside male(who the 10 yr old seems to like) not neutered but never see him spray and 3 ferals I feed every evening behind my garage in a large dog house and they seem to disappear after eating Now my 10 yr old male has begun to mark in the house(cats been around since may) I didn't even let him in yesterday after he marked on the corner of a bedspread (he has access to get into the basement and does do that and so does the black male he doesn't care for)they never seem to fight when together in the basement but the 10 yr old was walking up and hitting the black one often; the black one wouldn't fight back but now he makes a meow if my 10 yr old goes to wap him so he doesn't. The basement doesn't seem to smell bad but I can't have the house marking. I try to give the older male more love and attention and I tell him no when I see him starting to back up but there are many places(have a black light) and did clean them up with enzyme cleaner but when he is in he paces and paces and wants to mark just seem to be so erratic. This morning I let him in for a short time and he seemed a little more calm but wasn't in long and went to the door. This whole situation has got me bonkers I don't want him out all the time this winter when it is freezing(frankly I don't like cats out at all but that was what happened when I tried to keep him as indoor only once he marked the furniture but stopped when i let him go out again~I now have new furniture) I was trying to acclimate those 3 cats together(female 2 males) at least for being mostly indoors (but I don't want anymore in my house and do feel badly for the other stray and the ferals but like I said don't want anymore inside have health problems and having trouble taking care of all these) and also have a Lab and an indoor only female(spayed)~all cats are ok with the dog but the ferals and the outside one still a bit afraid around him)I bought Feliway have one in the basement and the kitchen I probably need one for every room but they are so pricey!Anyone else ever had this problem?Rehoming is not an option only because I have tried and tried no one wants any of them and our shelter is kill after 5 days..P.S. I know I probably should take him to the vet but I am running so low on funds at the moment having all these animals and having taken them for neutering and shots etc I will be trying to get him there soon. I was thinking of asking the vet for some prozac to try I also bought calming chews I have been giving him Thanks for any advice