They have judgements against the house for more than the value.   

A civil judgement is just a piece of paper unless you can use it for force payment.

She went to court and went through with an eviction and a judgement for $910 and I didn’t find out until we were looking for more space when our lease ended and we got rejected. it’s likely the very same thing is going on here. 

The eviction process here is actually very smooth compared to the coasts, it's about 6 weeks from posting a 3-day notice to bailiffs showing up at the door to enforce the judgement.

A good example is the S&P 500 Index fund VFINX - the S&P500 is simply the largest (by total stock worth) 500 companies on the market, very simple to know who they are and it takes little work to maintain a fund that invests in them, as there is no judgement or expertise involved - whoever the biggest 500 companies are, that's the S&P500.

I would also imagine that there could be some sort of fraud as well, being that you did not disclose this pending judgement during the sale.

The court awarded my claim of $2,700 I sent in the court judgement and they sent me a check for the amount I won.It totally was worth filing the claim.

I add the judgement lien add on as well to the full trans union for 47 total and feel like it gives me what I’m looking for.  

Don't let that factor into your judgement.

A court may take the equity of the house for a judgement.