Rental contract invoicing

Hi,

We are place in a country with high inflation and contracts are negotiated in US Dollars but we have to report to our Government in local currency. So, we have set the contracts with Base Currency = Local Currency, Trancation Currency USDollar and Invoice Currency = USDollar. The idea was to insert the contract details in USD and at the invoicing time the system would convert the USD amount to Local Currency based on current month rate. This way, the invoice would reflect the variances between the USD and local currency along the contract period (usually 2 years).

However, when entering the cotnract detail in USD, it converts to Local Currency using the contract header exchange rate and when invoicing it converts this Local Currency amount to the USD using the invoicing month exchange rate. So, we are getting currency covnersion twice. My doubt is: does anybody knows if this is working as designed? Also, have anybody already implented this scenario?