Rear addition with crawlspace

Hi,

I am considering adding an addition to the back of my house to increase the size of the kitchen and eating area. While this project is a few years out I would like to set some goal posts to aim for costwise, any guidance that can be offered would be greatly appreciated. Project is in Calgary, AB. See attached survey snapshot both annotated and not.

The current eating area is a single story gabled section as identified on the image. I would like to extend that out to be flush with the back of the sunroom (~2.13m) for the full width (4.27m, shown in orange). As part of this process I would like to flush up the sunroom to the extended eating area and move the current door (in red) to the back (in yellow). From the drawing you can see that the sunroom roof extends square it is just the doorway that is angled. I would like the addition to have a Crawlspace underneath (or if not cost prohibitive a full depth basement addition) to help keep the room warmer. There is a window well not pictured (drawn with green) that could be opened up to serve as the entrance to the Crawlspace. Also, in blue, I would like to increase the size of the other window well for safety purposes. Two heating/cooling vents currently terminate at the back of the house and would need to be extended back with the addition and some electrical reworks will be required including an exterior light and outlet, and potentially adding switches closer to the new exterior door. We would like the addition to have panoramic half height windows with a double sliding door for access to the deck. Continuation of the gable ceiling would be acceptable, but a terminating slope to 8ft ceiling height would be preferred.

This would be done in conjunction with a kitchen reno which will be mostly completed by myself but there may be opportunities for an expanded scope to assist with plumbing and electrical rough ins as well as approximately 1000 sqft of tiling (including the new addition). Removal of the current deck will be completed by myself, but please comment of cost of excavation for Crawlspace.

Please let me know if you have any questions. Thanks for any guidance you can provide.