I just went to meet the vendor, had tea and a chat for about an hour and looked all round.
He said he would love to see it become a Housing Coop like this. He envisages making a decision on offers not before the end of May or possibly into June, which means we very probably do have enough time. He needs to move out tho and needs the money to fund his retirement because he's been ill the last two years and sounds like he has no other income, so he really can't afford to extend the sale time period too much. He's selling by sealed bids partly because he definitely does not want it to go to a developer who would split it up into 4-6 flats and ruin it. As I expected, he's very, very sympathetic to our plan, and I think basically if we can get ourselves organised in time (by the end of May it sounds like) then I think he'd probably prefer to sell it to us, even if it ours wasn't absolutely the highest offer.
It needs more work doing than I first thought- the main thing is that there used to be another wing on the end, which was partly wood and eventually needed taking down, but there are still 5ft deep foundations and no need for planning permission to put the two story SW wing back again. The end wall where the old servants quarters were was not designed to be that exposed, so it's damp because it's exposed to all the weather. As a short-medium term fix, I think a cheap n simple way to fix that problem would be to make a scaffolding and timber frame 'glazed' with low-E ETFE plastic (which is v cheap and almost as good U-value as double-glazing) 'conservatory', and put a temporary door on the staircase opening on the 1st floor so that the heat gathered in the conservatory could be let into the upstairs and circulate around the house. Once the end wall is protected from the weather, the damp damaged parts on the inside just needs replastering and repainting. That much we could do ourselves fairly cheaply. It also needs a new boiler, but there's a working chimneys in the first lounge off the kitchen which could have a wood stove+boiler. There's also a big loft which ultimately could be converted into another bedroom as well, altho the design of the beams would make that a very big job.
It's extremely solidly well built in every way. It's absolutely gorgeous. With a bunch of young people working on it together, I reckon we could make it at least fairly comfortable by winter not too expensively and ultimately it's potential is even more amazing than I thought before I saw it.
I was mistaken about it being next door the old Baptist church which is another potential CLT site. Actually the church it's next door to is the CoE church, which apparently is quite High Church and also quite evangelical.

But the old Baptist church is just down the hill a bit, not very far away, so it would still work to operate them slightly connectedly.
Also, I didn't fully realise before just how close to the park it is- it's literally just over the fence, or down the steps and round the corner. My fiance and I both thought simultaneously independently that it would mean we could use the house's own garden for vegetables and a dog run, and use the park for lounging around on grass, etc.
I'm not so convinced now that there's really enough space for 4 young couples -it would be possible, but I'm now thinking maybe a mixture of two young couples and two older people or retirees -I've heard from a friend at Quakers who's hoping to set up a Housing Coop with a few older friends to support each other, and who expressed some interest in being nearby or mixing with younger people for mutual benefit. So I'm going to ask her if she'd be interested.
Please get in contact even if you're just interested and not sure you can or want to commit, I'm interested in the whole idea of co-housing and cooperative living generally, and talking to people who may actually want different things will help clarify my thinking around how best to organise this one at least.
Thanks for reading again!