After purchase, farmhouse/truck/roadsidestand features show in the collection book, and are 75% off the original price.

The original features are listed there, nominally priced 1000 coins, but available at 75% off that (since they were already installed, presumably).

However, if one of the customizations Maggie randomly offers is an Original feature (EG, farmhouse Original White walls) that has not been put back previously, Maggie offers it at full price.

This is a cosmetic bug only, having effectively nil impact on game play unless a player is foolish enough to spend a bunch of coins to nail down the exact behavior.