One caution. When I invested in my tractor, I went over the spreadsheet with my fiancé. She understood the numbers and buying the right size machine was not a problem.
If you buy something you "can afford" (or get away with) and it is not the right machine, spending a more money in a couple of years to upgrade can stress the relationship.
If you screwed up the first time, you lose credibility.
Nothing wrong with buying a machine that is a bit too small to get you started if both of you agree that it may be necessary to upgrade down the road.