Speaking as someone of the incredibly cheap persuasion: scrounging nice cut offs from constructions sites is a good way to get building supplies of up to 7’ or so.
Right now I’m hoarding enough to start a new shed....
You’re not cheap-—you are recycling!
I live in a tear down neighborhood. Fancy houses are springing up all around me.
I dumpster dive for their fancy wood. When the cabinetry goes in at the end is when the dumpster contains the nice finishing wood.
Also, I have found that the supporting wood that temporarily holds up the walls is of very poor quality.
The Contractors let you come onsite and peruse their scrap piles? Or do you wait until after dusk and take what you want?