Synonyms of the word 
RENT-FREE → UNPAID
rent-free
- adj. On which no rent is payable.
- adv. Without paying rent.
unpaid
- adj. Not paid for.
- adj. Of work: done without agreed payment, usually voluntarily.
If you are interested in words, visit the following sites :
- wiktionary.org/rent-free For complete definition of a word
- 1word.ws/rentfree to play with words, suffixs, prefixs, etc.