An RV is not an investment; it’s a depreciable asset. In short, monetary value is irrelevant. If you are “investing” money to resell it, that is an investment decision which, in this case and as others have said, does not provide a solid return. If you are “spending” money to make an existing asset “better,” that is considered a “betterment,” in which the value is the benefit that comes from the spending. In short, if you really like your trailer, it is solid, and will last you long enough to make spending the money on upgrades worthwhile, ignore the presumed “value” and consider the expenditure as you would any other expenditure that does not provide a monetary return; e.g. a cruise, night out at the movies, two week vacation with family, etc.