you need to consider thermal needs, privacy issues, light control, noise control, decorative preferences, size of window, room available around and above window, shape of window, budget...that is why a professional window coverings expert is the best to assist.

I am no expert, but it appears (from the wood, shape and handles) to be a danish teak dresser - they date from around the mid-late fifties and sixties. Don't think they are particularly rare (check for makers mark eg) Borge Mogensen/Sorborg Mobler?), but they are lovely, and very on-trend (similar new version by West Elm sells for $1099). Didn't find one exactly like yours on ebay, but similar vintage ones listed start at around AU $550-$600 and go up from there. A great thrifting find!

I just hope your opening is wide enough for what you want. If you need to make it wider then you will also need to consult a structural engineer for a lintel design to span the wider opening before the builder starts. You may want to do your research on stacker and sliding doors first to find a manufacturer that you like and tell your builder the colour and the manufacturer before he quotes. Don't leave it to your builder to decide as he will just get the cheapest. Get a builder to quote if you are using aluminium doors. They have to be measured precisely and ordered by the builder (who takes a risk if he makes a mistake when measuring). Do your research so you know what you want, and how it works, rather than get your builder decide based on what is easiest and cheapest to install. Dr Retro of Dr Retro House Calls/Dr Retro Virtual Visits

By your pictures you have chosen lounge settings. Is this your preference for this area, or would you be using space for actual dining and entertaining. I find that low lounges like the ones shown are not ideal for eating meals. You end up with a plate on your lap.