A one-off, or is the dam finally bursting?

10 Brookridge Drive, priced at $3.995 million, has a contract after 88 days. It’s a grand old house, but what catches my eye is that it was completely renovated in 2018 and sold to these owners in 2019 for $3.250. So far as I can tell, no substantial improvements were added in the past year-and-a-half, and the listing makes no such claim. So I ask: are prices finally spiking? I’ve been expecting that to happen simply because there’s so little inventory and such high demand. Basic economics would predict this but so far, it hasn’t happened. Maybe now it has.