Backstory: (Might be relevant)
Wife and I have found a colony of feral cats in our city, consisting of a mom and a litter of four kittens. We took an instant liking to them and from that point on for nearly three weeks went out every evening to feed them and try to socialize them a bit. When we had food they came out of their hollow, and as long as we sat relatively still, they were unafraid of us. We could also pet the mom and some of the kittens at times while eating. Mom was less scaredy in general, she sometimes burshed up to us while sitting there on her own accord.
We don't know the specific age of the kittens, but they are older than 2 months for sure (we'd guess between 3 and 6 months), as they eat solid food, have good movement coordination and they look more like small adult cats with some kitten-y features than the furballs with weirdly oversized heads like very young kittens are.
Normally we would have involved some organization to TNR the mom and socialize the kittens of which two we would have adopted for ourselves, but while there are some animal rescue/humane organizations in my country, also some in my immediate area, it seems to me that TNR has no significant tradition in my country, and maybe due to Covid or just general lack of funding or caring, multiple phone calls/emails to these organizations were entirely fruitful and we were basically politely or not-so-politely told that they are overburdened, can't help us, have no advice or traps or volunteers for us and we should basically feck off.
So after we realized no one's gonna help us, we took two of the kittens by letting them walk into carriers and shutting the doors on them. We previously bought some stuffs and also read quite a few articles on ferals, but we were still woefully underprepared as we later learned, and we have some issues. Some behaviours we don't know if is normal and uncertainty regarding how to proceed. Also neither me nor my wife have ever kept cats at home before. Wife's family had semi-feral cats in the garden, but they weren't indoor cats.
I am listing some of the problems and screw-ups here.
Lots of advice articles mention using a mostly empty "safe room". Our flat is relatively spatious, but we absolutely do not have spare rooms. Every single room is completely utilized, the best we could do is to move out of the bedroom to the sofa in the living room, but having a bed with lots of nooks and crannies in the bedroom would be counterproductive and we have no way of removing that bed from the bedroom.
I have read that it is recommended the feral kittens to be separated in separate enclosing spaces. Aside from safe rooms (which are unavailable, as I have said) I have read using rabbit cages, large cardboard boxes, large cat carriers, etc. We made a makeshift enclosure by barricading a corner of the living room. They kittens were not to be separated just yet, we wanted to take them to the vet the next day, and figured they'd probably adjust better if they had each other. This might have been a mistake. Also due to our screw-up they escaped confinement and darted throughout the flat (the containment would have been insufficient even if there was no screw-up on our parts, we seriously underestimated how high they can jump).
The kittens thus have free reign in the place. This is the third day the kittens are in our flat, we managed to block off most of the really inaccessible or inconvenient/harmful hiding places in the flat (for example the baking sheet holder in the oven, and the kitchen counter which is impossible to be removed from the wall without seriously dismantling the flat). Now they are hiding in places we can see and we can access, but they are still not contained.
The kittens are extremely scared of us. Part of me is not surprised since they have a huge, unknown place to them, but during the day/when we are at home, they absolutely refuse to leave their little hiding places. They huddle down into a small, compact shape and do not do anything. I tried to spoon-feed them tasty wet junior cat food at times. Sometimes I could get them to lick some of it off the spoon, but in general, they also wouldn't eat during the day, and we couldn't get them to come out of their hiding spots by either treats or toys.
I have frequently read to use wet food/treats to get them to loosen up and trust us, however during the first two days they completely refused to eat/drink/eliminate and I got worried for them so I usually put out tasty wet food for the night. Dry food, litterbox and water is always available. They do eat during the nights when wife and I are in the bedroom and the lights are off, so I am not worried they die of starvation but I don't like this development because I want them to associate tasty food with us. Their appetite in general is much less than it was when we just visited them near their den in the city.
Advice on the internet seems to be contradictory regarding handling. Some sources say that they should only be handled if they come to us, other sources say that handling needs to be forced to a degree to get them accustomed to us. Regarding our kittens, this is a mixed bag. We frequently talk to them in soft tones, and if they are huddled down in their hiding spots during the day, if I approach them slowly, they usually tolerate it if I stroke them gently. Frequent advice is to pick them up, wrap them in a blanket into a "burrito" formation and stroke them gently while in our laps while talking to them softly. They don't like getting picked up and usually start hissing/scratching/squirming, and thus covering them with blankets to get them to feel safe is very difficult, because we cannot get them to lay on blankets and if we approach them with blankets, they get scared shitless and run off. We also stopped trying to handle them a lot aside from some occasional stroking when they let it, as we are worried we are only stressing them out more and they will get more, rather than less feral. Also while they do tend to let us pet them if we calmly approach them in their hiding spots, they never come out or come to us.
We put off taking them to the vet for now, because until now they could hide in places we couldn't get to. I have an appointment to the vet on monday. Since they hide now in accessible places, we can grab them by the nape and put them into carriers if the need be. I am a bit terrified to do that since that would probably make them hate us even more, but this needs to be done. But afterwards, I am not sure about anything anymore:
Cages. Yay or nay? I have found a large pet-accessory shop that have relatively large rabbit cages. They are expensive but we do have enough economy to buy two of them. I am of the opinion that once we are done at the vet, we should cage them separately, put some blankets on the cages, and in each one put a hiding spot and dryfood/water/litterbox. My wife is for some reason opposed to the idea. I don't really understand why but the cages are usually recommended so that they have a smaller space they are not that afraid of. And the way things happened, good or not, they already have access to the living room and the antechamber, so I am also not sure if it is needed. Should we cage them?
How can we get them to trust us more and come out? Is it ok to withhold food or at least wet food from them unless they take it on our terms? As I have said before, I was worried they are so scared they'd rather starve than come out into the open, and as an inexperienced person, I have no idea how malleable they are this way. I am worried if we only give them wet food if they come out to us, they'd simply wither away rather than come closer. So right now they always have access to wet food as well.
Is it ok to force a bit of handling? Of course not if they are so scared they are hissing and scratching, but maybe try to put a blanket on my lap, grab a kitten by the nape and put him/her down on the blanket, wrap them up, and try to get them to calm down. Or should we just stop touching them until they get more comfy?
I suspect we have missed the window when they are easily socialized, so what are the likely results? I am ok if they will never be absolute 100% snugglebunnies but there is a difference between them being a bit timid and scaredy but otherwise finding our presence and touch comfortable and them behaving the same way they do now all the time. When to give up and when to proceed? Can taming fail completely? What should we do if they absolutely don't come around?