Should I purchase a blogspot blog?

Hey,

A guy offered me a blogspot blog. It's worth more than $800. I am really skeptical over here. I am worried about three things.

1) First up, google can delete the blog any time as per will and wish
2) Secondly, if I get a proper domain for the blog, I might loss out on the traffic and revenue.

I am willing to live with the above 2 risks because I know that many blogspot blogs have survived for years. But, still looking for some suggestions to come up with a well informed decision.

Now, my main concern is this. What all details should I ask from the buyer to be absolutely sure that the blog will be all mine. To my understanding, he just needs to provide me his gmail user name and password. The thing that I would like to know is that is there any way that the guy can report loss password to google or do something else to gain the blog back, despite me changing user name and password after the deal. If you guys know that gmail also offers a service called mobile verification to recover password. I don't know the user personally, so I am just wondering how to handle this deal.

EDIT- he mentioned he will transfer the blogspot from his account to mine and then remove himeself from adminstrative rights. Now, I am wondering when you transfer one blogspot to another, does the blog url change?

Thanks in advance for your suggestions.

I need some answers on this as well, as I own a blogspot blog that when its completed, i want to sell it as well, and want to know how to go about finding a suitable buyer, and how to transfer it out of my account. I dont want to interfere with it after someone else buys it.

Never do it, if Blogspot gets to know about this change, the blog will get removed.