Just got one today. I didn't pick up, and they didn't leave a message. Caller ID said "Out of area". When that happens it usually means that it's some sort of spoofed call, but not always. Whitepages.com posters classified this number as "Suspected spam".
Received call from number. Let it go to VM. Called it back later in the day and got a recording saying that they have "an important matter to discuss about my vehicle" and to wait on the line for an agent to answer. Needless to say I hung up. I HAVE been looking around for a used car in the last couple of weeks but there was no info about who they are so I would consider it spam.