If like me, you're not an artist and you've never had the time nor inclination to drill the 36 million Blender keyboard shortcuts into your brain, you might find some tools that have been shipping with Windows 10 lately quite useful.
Both have different strengths depending on what sort of shape/design you're aiming for. Both can export in .obj format for use in Unity, complete with textures. I found Paint3D had more flexibility, allowing you to literally draw shapes and extrude them into 3D, then manipulate them. You can paint directly onto the object with a range of brushes. No custom textures, but that's where 3D builder comes in.
Paint3D doesn't tend to export right straight into Unity, so I exported in .3mf format, imported into 3D builder, added any textures I wanted and then exported to .obj format from there. As usual you'll need to set their scale to 100 or 1000.
Once you've exported more than one model into Unity their materials will tend to get jumbled up, so it's just a question of finding the right material in the folder and dragging it into the right slot in the materials list in the inspector. A bit of a pain but quicker than scrabbling around in Blender.
I made this little chap in about 5 minutes, which would have taken me several ice ages in Blender.
