Hi Marl!
Going by taxi, the cost depends on the traffic but it'll cost 4-6 euros maximum.
Gran Vía and Uni. San Pablo Ceu, Fundación Jiménez Díaz are quite near and public transportation is really good. You can also take the 44, 1 or Circular busses to go there from Gran Vía.
UCM (Universidad Complutense) is a bit further (only a bit) and covers a wider area but you should expect more or less the same range of prices.