Hi Sean,
I don’t know of any (affordable) long term parking facility anywhere– long term at the airport is $15 a day. But like many things here you can get creative. Perhaps the person/dealer you are buying it from will store it for a small fee. Or, if you know someone in the area (or can network to find someone) who is willing to keep it, that might work. Or, just wait until you arrive to purchase… unless, of course you found the perfect car already.
I will ask around for additional solutions and let you know if I find any.
Best of luck,
Greg