Good luck getting it to start, gas goes to [censored] after 90 days, unless stabilzer was added. Anyways letting it sit is bad for all fluids, plugs and wires, secondly nothing was lubriacted, unless your drove it for 25 feet after 15 days, also the battery is most likely shot unless you disconnected it.

Good luck selling it, doubt you will if the buyer finds out about its history.