Would you have to pay for overage on miles?
I think (depending on the buyout amount) that you might be better off selling it yourself, rather than spending the time and money to return it to stock so that you could turn it in at lease end. Looking at the mods you did, they all pretty much are bolt-ons, so it is reversible but you really never intended to return it, did you? Otherwise why do all those mods on a leased car? Can you do all the work yourself so you don't have to invest in a lot of expensive labor?
If you need something bigger and buy a Clubby or a Countryman, few of those mods will transfer over so not only are you doing all the work, then you've got to sell all the parts.
I think I'd look very carefully at what cars like yours are selling for in this market, then decide which way this all makes sense. Are heavily modded cars like yours easy to sell in your market area?
