WOW that is some detail there!!! I'm sorry but I can't answer your question.
You could get them engaged now, if they aren't already, and have long engagement. Have him sell the place he is currently at, along with the belongings. Keep what you don't want to have to replace or just sell it so the house just don't sit there empty. Then just dirt cheap with putting things into his new place.
Then have them both be working a little harder on their career goals skills and get a little ahead in the department but don't lesson the effort for the rest of goals. For example, the writer career is going to have you writing all kinds of books. So put emphasis on the writing skill, plus he'll be earning money from selling books. Then pick another skill that is profitable, like fishing or something, and sell what he collects or makes. You can even work for tips with some skills. I know once you get a high DJ skill, your sim starts bringing home a lot of money. The most my Sim made was 2500 in one night but averaged 1500 to 1800 a night. Have her do the same so together, they are both saving money for their wedding, honeymoon and the expense of upgrading her home for when he moves in.
