Plan to sell next year, travel for a year, then buy again in year three while keeping property tax basis (55+) — thoughts?

Solid plan. The one detail to nail down before you build the timeline around it is the property tax basis transfer window. If you can afford a year of travel and still feel confident about buying again afterward, you're clearly in good shape. In California, the over-55 rule that lets you carry your prior tax basis to a replacement home comes with a time window between the sale and the replacement purchase. The general understanding is that the window is a couple of years, which would comfortably fit a one-year trip. Rules like this have specific requirements and have changed over time, so don't rely on memory or a rule of thumb. Confirm the current window and conditions with the county assessor or a tax professional before the whole sequence depends on it. Get that one detail right and sell, travel, then rebuy works nicely. The tax-basis savings is often the most valuable part of the whole move.