For my dad's birthday I found a model on Thingiverse that had similarities to the Parthenon in Greece. I printed in micro scale to get a sense of what it would look like (1.2"x0.8") before blowing it up about as large as my printer bed could handle. When it finished, 15 hours and 50 minutes had elapsed.
Some things I learned with this scale;
1: The edges will warp on large pieces, so I either need to use a raft/brim support structure to account for that, or use something other than painters tape as a bed layer (the solution I'm going to go with is using Kapton tape)
2: I need more patience with long prints