What should I include for additional accommodation when applying for a Thailand eVisa if I only have a hotel booking?

You dont need to apply for a tourist visa most passports are visa exempt for 60 days. If you have a hotel booked make sure you get the address for the TDAC you have to fill out

tdac.immigration.go.th/arrival-card/#/home

This has to be done within three days of arrival if you do not they will have you do it before you are allowed to enter saves time.

When you get to the hotel if you are planning to stay longer then 60 days or upgrade your visa to something else ask the hotel to provide a tm30 some will some wont.

Tm30 are for people here longer then 90 period of you intend to stay past that for any reason with approved visa

Just make sure to add at least one accomodation. They are not super strict about it (from my experience). No need to put like 2-3-4 Accomodations.

Most embassies don't ask for additional accomodation.