When we went to the Detroit Consulate the lady in the visa department gave us their Lettra di Invito form and said that form is acceptable for us to use with our extended stay visa application if our friends in Rome are allowing us to stay at their home with no rent charge. We took that form and Valerie translated it to make sure we knew what it said and that there wasn't anything in it that might be a problem. We then imaged the document and emailed it Sunday night to our friends in Rome.
Valerie's parents are currently in Gaeta, south of Rome, and they were able to meet with our friends at the Fiumicino Airport before Valerie's mom boarded her Wednesday morning flight and obtained the signed Lettra di Invito and necessary identification documents. We now have the housing documents they said we need for applying to the Detroit Consulate.
Since we are changing our residency to Ohio we will need to obtain Ohio drivers licenses and update our financial documents to our Ohio address. Once we have all of these items we will be ready to drive to Detroit again and submit our Extended Stay Visa application, hopefully at the end of next week. The consulate told us they take 2-3 weeks to process the visa application.