Price both alternatives. The potential structural changes doing it later will most likely kill that option.

Photos?

with one is 12 feet sliding stacked door

this one is a 8 foot long door with one operable panel. along with that there is a 6 foot window on left

Is the budget a consideration?

We did the double sliding doors where we have the two panels on each side as fixed but the two doors in the middle slide open. For us, it was a cheaper option than the stacking panels (which is really cool but expensive) and gave us a larger opening than just one patio door.

Does this door open to the outside or to a screened porch? I love seeing the English use these folding doors in the UK, but it appears they do not have the insect problem we have in the US, and also have a tolerance for wildlife coming inside that we also do not have. I don't want a bird/rabbit/skunk in my house. Some form of slider allows for screens.

I don't want a bird/rabbit/skunk in my house.

Let alone the foxes, rabid coyotes and the occasional moose that frequent our neighbourhood!

We installed two LaCantina doors a few months ago. The 144" x 96' cost $10,200 plus $1500 install. Our general contractor installed the LAM header. We also installed a 158' x 96", it cost $11,530. I dislike the screens La Cantina sells. We just ordered Vista View retractable screens. Centor makes nice doors with a nice hidden retractable screen, but buying two of those was just too much more money for us. I'm very happy with our La Cantina doors, we are in Southern California so they are local for us.

Keep in mind the categories of expenses involved in something like this:

--The structural costs to properly frame the necessary opening;

--Any mechanical or electrical costs which may be required for rerouting any existing systems;

--The costs of the doors, plus frieght or transportation;

--Installation

Good luck on your project.

It's not something you want to do later. If you want it - get it now. And $11K sounds too cheap. Does your builder have experience installing this kind of door system?

Do it now or forget it IMO.

The number sounds viable for a 12080 stacker including properly skilled installers. It depends on the brand, construction type (wood vs aluminum) glass composition, etc.

A retrofit might be 1.5-2x this cost due to multiple finishes on both sides that might have to be redone and a higher load of management not spread onto a larger job. (I'm not currently set up to do remodels & retrofits).

I have a home nearing completion with a large Fleetwood install of 6 doors & 13 windows.

If you want a wide opening, what about the standard mechanism with a two panel 8' door? Or, increments of 3 going up to 12', that would allow the center panels to open.