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With the emergence of multimedia applications with stringent requirements, like IPTV, the need for end-to-end Quality of Service (QoS) is increasing. In this paper, we investigate the problem of how to route high QoS flows with end-to-end QoS guarantees in a Path Computation Element (PCE) based architecture. In this architecture, three main types of path computation methods have been proposed: methods based on aggregated representations of the network, methods using predetermined domain (AS) sequences or methods using only the knowledge of the intra-domain topology as well as of the inter-domain links connected to the domain. The last family of algorithms is called ad-hoc methods. These methods have not been extensively studied in the context of the PCE architecture yet. This paper has two main contributions. First, we propose a new Ad-hoc PCE based Recursive Inter-domain Path Computation method (ARPC) that dynamically determines the AS sequence crossed. This algorithm integrates complexity reduction mechanisms. We consider an example application of this algorithm for simultaneously minimizing the traffic forwarding cost, guaranteeing a minimum bandwidth and optimizing an additive metric related to load balancing. We assess the performance of this algorithm with regard to these objectives. A simulation study demonstrates that the complexity of ad-hoc methods is reasonable, in certain topologies. Thus, these methods deserve further study. Second, we propose that PCEs in a domain are aware of the economical cost (price) of the inter-domain links connected to this domain. We demonstrate that this additional knowledge allows the implementation of interesting economical strategies. For that, we implement a detailed example.