Hello and welcome to CF!
As you know, it is the sacramental marriage in the Church that matters.
These don't have to have the tens of thousands of dollars of costs associated that some people spend on weddings. Of course the reception will cost money, and you'll likely want some things - maybe a wedding dress and rings - that will cost some, but from what I've seen, a beautiful Orthodox wedding doesn't have to cost nearly as much as your typical venue wedding.
Many times the Church will have items you might be able to borrow - tablecloths, vases, etc. - and if the fellowship hall has a kitchen they may well be able to let you borrow some things associated with the food, so especially if it is prepared on-site you can save a bit. And so on.
As to living arrangements - please don't live together, just for the sake of saving money. Some priests won't even marry couples if they are living together without counseling and rectifying that situation. I am not sure, but Church canons may have something to say about that.
My daughter is in the position of saving money for her future as well. She has two female roommates, and her young man lives a couple of miles away with two male roommates, so the money situation is no different living apart. That would allow you to save money at the same rate without putting yourself in the way of temptation or tempt others to think evil of the situation.
And there is some wisdom in marrying sooner, as long as your plans are sure with the young man. There's no real reason to wait in that case, unless it involves being sure not to have children too soon if you're not able to provide for them yet.
I hope you find the way that works. Again, welcome to CF, and God be with you!