-We study the statistics of the local resolvent and non-ergodic properties of eigenvectors for a generalised Rosenzweig-Porter N × N random matrix model, undergoing two transitions separated by a delocalised non-ergodic phase. Interpreting the model as the combination of onsite random energies {ai} and a structurally disordered hopping, we found that each eigenstate is delocalised over N 2−γ sites close in energy |aj − ai| ≤ N 1−γ in agreement with Kravtsov et al. (New. J. Phys., 17 (2015) 122002) . Our other main result, obtained combining a recurrence relation for the resolvent matrix with insights from Dyson's Brownian motion, is to show that the properties of the non-ergodic delocalised phase can be probed studying the statistics of the local resolvent in a non-standard scaling limit.The theoretical study of the non-equilibrium dynamics of isolated quantum systems has attracted considerable interest in recent years, partly due to advances in experiments on trapped ultra-cold atomic gases [1]. One of the most fundamental questions that arose is about the applicability of statistical mechanics to quantum systems in presence of interactions and disorder, and the related Many-body localisation (MBL) transition [2]. A system is in a MBL phase if taking interactions into account the many-body eigenstates are localised in Fock space. The Fock space can be seen as a lattice with connectivity determined by two-body interactions. Its structure is that of a very high dimensional lattice where loops are scarce, therefore reminiscent of the Bethe lattice and random regular graphs (RRG). Starting from the pioneering work [3], Anderson localization on such lattices has been considered by many as a simplified case to study questions related to the MBL transition. It attracted a lot of attention recently [4-6] because it could provide a test ground to analyse the delocalised non-ergodic or "bad metal" regime, which was predicted as an intermediate phase separating the fully delocalised and the MBL phases [2,3]. In (a) davide.facoetti@kcl.ac.uk this regime, eigenstates would be delocalised over a large number of configurations, but which only cover a very tiny fraction, vanishing for large system size, of the entire Fock space. Although the existence of the MBL transition is now well established (at least for one dimensional systems) [7], the understanding of the delocalised non-ergodic phase is far from being completed. Some numerical results seem to indicate its presence in many-body systems [8,9] whereas its existence on Bethe lattices is under intense scrutiny and debated [4,6,[10][11][12]. It is not clear at this stage whether the sub-diffusive behaviour found before the MBL transition [13][14][15][16][17] is somehow related to it.Given this state of the art, it is therefore useful to study simpler models that could provide a playground to explore its nature and sharpen the questions about it. With this aim, the authors of Ref. [18] proposed a random matrix model, the generalised Rosenzweig-Porter (GRP) model,...