Need Clarification on purchasing at Sheriff sale

[Tyler Smiarowski]

May seem like a basic question but wanted to verify...

If I were to purchase a home at a sheriff sale...as long as I purchase the "1st" mortgage on the home I am ok? (not including back taxes, mechanic liens, etc). Regardless if it has a "2nd" mortgage on it?

The big mistake to make as I understand it is to purchase a 2nd mortgage at a sheriff sale and being in second position on the property after the auction?

I would think that if the judgement amount on the home is higher than the ARV, for example the house has a judgment of 100k but only worth 90k this would be a good indication that the foreclosure has been brought on by the bank carrying the 1st mortgage on it?