I don't know when your house was done, but I just typed in Seeno Homes Pittsburg CA plans and a ton of plans and elevation drawings showed up. You might do that and see if one of them matches yours. If your house was drawn up recently (ca. mid-90's they probably still have it on computer.) We're required to keep things for 10 years, but now that an entire drawing set for a little house might take up 875 kb, I keep stuff a lot longer than that. If it was hard-copy they might have tossed it, but a developer I would think would keep it around because they make money by not re-inventing the wheel. If you need new drawings done, hire an as-built co. They do it cheap/fast/accurate. I gotta group who are great, PPM (precision property measurements). I can explain to you what to ask for or you can just go for it. You don't need an arch to draw up existing conditions...too much $$. Srsly. Unless you want it all "artistic". Then you might want someone with some hand-drafting experience, and that's getting harder to come by these days. I usually take my computer drawings and run it through a "sketch" filter on Photoshop to make them seem more artsy-fartsy if I need.