Taxi travel is affordable in Moscow, but be aware, there are many illegal taxis, who can rip you off. But now there is an easy way to be sure that your taxi is an official one.
Simply download the app “Yandex Taxi” in Google Play or Apples app store.
Within the app you can easily select your pic up point as well as your destination. Further on the app will show you directly the estimated price ( In general, the app is constructed like UBER but has a much bigger coverage in Moscow and usually within 5mins you will be picked up). But you can also pre-order the taxi for a specific time and date.
Further on, fares from inside the MKAD ( Moscow circle road ) to Domodedovo, Sheremetyevo and Vnukovo airport and vise-versa are fix priced at 1000 RUR.