The goodman of the house (tōi oikodespotēi). A non-classical word, but in late papyri. It means master (despot) of the house, householder. The usual Greek has two separate words, oikou despotēs (master of the house).
My guest-chamber (to kataluma mou). In lxx, papyri, and modern Greek for lodging-place (inn, as in Luk 2:7 or guest-chamber as here). It was used for khan or caravanserai.
I shall eat (phagō). Futuristic aorist subjunctive with hopou.