Determining numbers on a 4+ property

[Donald S.]

Hi everyone, 

So I found a 4-plex in my area that looks like it has decent numbers, but that's going off of the seller's provided numbers on the listing. So if I'm new to buying multi families, how can I verify the expense numbers that he claims are "2016 actual values"? I've been looking on Loopnet and there are a few 6 and 8 families available as well so how to verify or adjust their numbers will be valuable information. 

I'm just wondering if the numbers look so great, why are they still on the market? I've heard that loopnet is where deals go to die, but haven't heard why? 

So if anyone can help me out on what numbers to look at and how to verify they're true? Also I've seen insurance quotes on a lot of people's property analysis of 75-150/month for 2-6 family properties, I've gotten actual quotes from USAA and it was 215 for a duplex, I imagine 4+ would be significantly more. What coverages are people getting with such small insurance premiums? is it normal for insurance to go down/door the more doors on the property?