@ThomasM125 From IRS 2019 Instructions for Sch E (Line 2) https://www.irs.gov/pub/irs-pdf/i1040se.pdf this sounds more consistent with what I would think makes sense. AND it's not consistent with what TT told me. Reading this I think personal days is 334, not zero (and the section below copied from IRS, bold and italicized, is DIFFERENT in the TT On Demand Tax Guidance for Personal Use description I copied and put in the post above). I hadn't tried to rent it prior to when when it got rented (no ads placed).
A day of personal use is any day, or
part of a day, that the unit was used by:
• You for personal purposes,
• Any other person for personal purposes, if that person owns part of the
unit (unless rented to that person under a
“shared equity” financing agreement),
• Anyone in your family (or in the
family of someone else who owns part
of the unit), unless the unit is rented at a
TIP
fair rental price to that person as his or
her main home,
• Anyone who pays less than a fair
rental price for the unit, or
• Anyone under an agreement that
lets you use some other unit.
Do not count as personal use:
• Any day you spent working substantially full time repairing and maintaining the unit, even if family members
used it for recreational purposes on that
day, or
• Any days you used the unit as your
main home before or after renting it or
offering it for rent, if you rented or tried
to rent it for at least 12 consecutive
months (or for a period of less than 12
consecutive months at the end of which
you sold or exchanged it).
