ref acmi: jar modules are available each with specific requirments
..for instance european jar operator wet leases a non european jar operator. the module is designed that the 'lessee' performs an audit,submits the documentation ,insurances.certificates etc of the lessor to the goverment or aviation body of the lessee including a copy of the contract between the 2 parties the govt or CAA then approve the lease based on the legality of the lessors approvals and that the lessee will ensure that the lessor complies with the limitations of the JAR,the only sticking point was the issue of the FTL,and this was also the issue with US operators who may stipulate that they would comply with the JAR's providing they did not infringe on their own FAR's.
so i recommend if you make a wet lease contract,ensure your block hour rate includes crew positioning/de positioning and hotac/surface transport ,therefore you can passively conduct compliance and the lessor is responable for any addit cost of supplementing the crew slips and rest periods to comply with your authorities regulations with out passing on the costs to you the lessee
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