Wow. 46 replies in just over 12 hrs! Cat's Win!!
Good for you - sounds like a tough challenge.
I have one feral I brought inside after watching him evade monsters for over 2 years.
He went thru all kinds of hell at the vet, and had to be quarantined (he bit me - my fault not his).
But the flea treatment, ear de-miting neutering, & other stuff made him into a nearly 'new' cat!
(see
Boraxo for flea followup treatment of bedding and carpets)
He was SO happy to be clean, safe, and have a new warm home and food many times a day (food is still his main 'worry')! He's now one of the cuddliest, purriest, thankful-est cats I've ever had.
But, it did take him a month or so to find his place(s) - I started him in a guest room with a custom 'prison' door so he could interact but not fight with the other cats. He took to litter immediately, no problem, though he's pretty serious about burying it!
He also spent the first two weeks or so sitting in the window looking out, and occasionally attacking the window screens, but he stopped doing that once he realized he doesn't have to constantly be one the alert for dogs and coyotes anymore.
He's now starting to 'chub out' a little bit, but is still strong as an ox, and bit on the 'rude' side: Boom! and He's There head butting you right in the nose! Street wise, I'd say, compared to the other 'domestics'.
YES to getting him fixed - otherwise he'll start spraying like crazy!!
(See
OdorMute for fixing pee issues!)
And, just last week I took in a stray Siamese kitten, and still no responses to ads I've placed, and no reports anywhere of anyone looking for her. Best guess is she was an apartment move 'leave behind'...grrrr.
(Here there are
laws to be followed regarding Strays and Lost Chattels - you may want to check in your province?)
But she's clean, no fleas or ear mites, vet said she looked really healthy for 6 mos.
Found a young couple who going to adopt her this weekend - very glad to have found a great new home for her!
Several others here who work with feral re-homing (or neuter and release) have said that sometimes ferals take a long time to adapt and find their place at home inside, and sometimes there's just no choice but to re-release.
One example took nearly two months to stop hiding & 'come around' but has turned into one of the most affectionate cats ever! I think 'reliable food' is the best way.
BTW, I don't use spray bottles - it teaches the cats there is still something 'to fear' inside, and will associate
You with it.
I use one of these horrible smelling things (it also is a great way to 'be notified by stink' that he's been near the speaker!)
https://www.amazon.com/gp/product/B01M3SITWO/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
to keep the new feral off the speaker grills, and found he really loves this kind of scratching post!
https://www.amazon.com/gp/product/B01LY5L4ON/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
Since you are getting the friendly and affectionate stuff, I'd say you'll be fine - just give him time to adapt and be sure he can 'forget' this old survival ways.
Good job!!