Here's an plan from an N scale model of 20 years ago that I enlarged to HO and built the MOW shed. Seems the old wood sheathed boxcar had some life left.

I used evergreen scribed siding for the building and doors by using the scribe and snap method of construction after measuring the Grandt Line door/window openings. The roof is cardstock with masking tape tar paper strips. Wood is stained via the ole rag between fingers and pull the wood through the wet paint/rag method. I built a jig to make the leg structures go faster and keep them uniform in size... :-)

Paint is tuscan red with trim of flat olive green. Much of the trim is leftover AMB laser kit peel and stick stuff. Neat. Window glass usual clear stuff. Smoke jack from parts box. Weathering is chalk. About 10-12 hours to build.