I probably would steer away from black if you want to keep the country theme

If you are establishing a sustainable/organic/permaculture type garden, then a chicken tractor can be pushed all over the yard to benefit both the chooks and the soil. As well as that, or instead of that, you can make a secure enclosure for them to run in the day, fenced in chicken wire, with a fully enclosed, warm house with perches at night. Instructions for both types are on the Internet. We let our poultry roam free range in the gardens at weekends, but not on weekdays because of our Jack Russell cross dogs, who have already killed one duck.

We had timber tri-folds (also facing north) in our previous home and whilst our landlord sanded and re-finished every couple of years, they didn't stay fresh for very long and it affected the integrity of the timber too (slight warping and 'furring'). I used some Haymes Exterior Solarshield recently and it was brilliant over very poor quality timber and I noticed it's guaranteed for 20 years?! It was acrylic and very easy to use, but has sealed the timber beautifully. It may be better option for the longer term if you're happy with the look of painted. It would look lovely and one less thing to worry about!

Window coverings are an important part of keeping your home cool and heated in summer and winter. The cost should of been part of the budget originally. So areas like an oversized pantry, or an oversized walk in robe, could be reduced to allow for more important details that impact the long term comfort of the home. I suggest you do all window coverings correctly according to their orientation and use. Even if you have a temporary window treatment until you can afford the correct coverings for long term benefit.