now, where is Maxim Trulenko's hideout ?

the only puzzle left, and here it is page 298, i bet even lee child himself did not know yet, while he was writing about it, so far, therefore, the interesting question is, where is it ... should be not too far away from the Ukranian HQ; should have windows, with a view; should be anonymous enough; should be securely guarded ... well, where is it ...