I was busy last night when I answered, so let me clarify today. When you hire a national chain to get you a BPO, they are hiring out locals to go get the job done. So you might pay the national service $100 for a drive by BPO. They are contracting a local for $30-$50. My opinion is that the local that is happy with $30-$50 to drive around town isn't much of a realtor. When I get the seller's BPO, they come back with the worst comps out there. Half the time, they don't even do a drive-by. When I have paid for BPOs from nationals, I've gotten some real losers that won't get out of the car to check anything out.
Personally I take the time to build the relationships and build teams in the cities I invest in. I pay them top dollar to go out and check my properties to, so I make it worth their while. My teams get out of the car. They'll check out the back yard. They'll talk to neighbors. If the property is vacant, the'll get pictures through the windows, or if they can get in, they will.
Building these teams slows down my progression to new towns, but I feel more confident in what I buy in the towns that I am in.
If you just need an occupancy check and you don't have a team in place, I use First Rate REO. A big firm that caters to the small investor. They do door knocks, inspections and property preservation, but they do not do valuations.