I believe putting in new windows tells the buyer that you did more than aesthetic repairs (even though replacing the windows helps).

I would definitely want approval over the design and construction.

Just curious to how many Realtors on Biggerpockets have Designations?

Perhaps they were having CSS problems when I looked at the site, but that's no-doubt one of the the worst designed websites I've seen in my entire life...For that reason alone, I wouldn't consider using it...

Dave how much did you pay for your site design??

1) the house needs to be listed and dated before the purchase contract is signed2)anyone the homeowner designates can negotiate depending on the laws in your state.

No structure, whether residence, accessory building, tennis court, swimmingpool, antennae (on a structure or on a Lot), flag poles, fences, walls, exterior lighting, or other improvements, shall beconstructed or maintained upon any Lot and no alteration or repainting to the exterior of a structure, with other thanthe original house paint colors, shall be made and no landscaping performed unless complete plans, specifications, andlot plans therefor, showing the exterior design, height, building material and color scheme thereof, including paintmanufacture and paint chip, the location of the structure plotted horizontally and vertically, the location and size ofdriveways, the general plan of landscaping, fencing, walls and windbreaks, and the grading plan shall have beensubmitted to and approved in writing by the Architectural Control Committee, and a copy of such plans, specificationsand lot plans as finally approved deposited with the Architectural Control Committee.

I've actually used an epoxy formula designed for this purpose.

Bill Gates designing a new toilet?

All ways design on a dime just because you have the money does not mean you have to use it.