жены(a person related to one by marriage e.g. one's brother-in-law, mother-in-law etc.); свойственник(a relative by marriage or through affinity); свояк; сват(The expression "co-father-in-law" is rare and is found primarily in translation. In conversation, the generic "in-law" is generally used, with context left to disambiguate. 4uzhoj); сватья(The expression "co-mother-in-law" is rare and is found primarily in translation. In conversation, the generic "in-law" is generally used, with context left to disambiguate. 4uzhoj); сваха(в знач. "сватья" 4uzhoj)
флигель(same as guest suite. "We have a floor with a separate bathroom devoted to Airbnb. They use the same front entrance as we do to our home' (Airbnb) АсяАся)