I watch a few things I am sure I am missing alot but here are afew ideas
Here on the tax deed resale I see if any liens stick with the property usually they tell you
I get whatever info I can find online,and /or from the county
What the county values something at may be close to reality , or to high or low so check a few in the area that actually sold recently to give you an idea of value.
if something checks out and I may want it
I will ACTUALLY go LOOK at it ,see if anyone is living in it and maybe talk to them awhile or a neighbor , and check out the neighborhood (you can just say your thinking about buying something in that area but usually they know what your doing)
Try to see inside if you can, I have had tenants invite me in and I had several who pointed out what they thought was wrong with the place.
If its something I may want I put it on my list with price I am willing to give.
Here some are paid off before the sale so you waste some time on them
I get some in rural areas
Sometimes the photos county uses are not recent and the house may not be there or other things are gone or the photos may be of the property next door or another property the person owned
Some county's here will show or sell you an aerial photo of the property and the property lines are in yellow(3 or 4 last year the outline they showed were wrong) You find out later if you have it surveyed.
Some times what looks like shared drive way isn't you have none.
Or the lake house that you looked at and now have the deed to
you learn the road leading to it belongs to the neighbor and abc road was never put in. (Usually here the county lets you know if something is landlocked,but they may not mention road isn't there) I talked to the county and they have no plans of putting in a road but I can at my expence
The neighbor fenced off where the actual road goes, and they keep the place mowed. :)
Within a day or two of the sale I go and look the best over again
Some get trashed or things disappear or burn just before the sale
On one a large metal building was gone or it could be a mobile home
Sheds ,the well or carport
Hope this helps you