Dealing with an eye-sore from a neighbor. Impacting interest.

[Garen T.]

How does everyone deal with problems that are caused by problem neighbors.

I'm going to be listing a duplex as available in about 6 weeks. However, the lady across the street from me has an RV parked in a way that is ugly and not fitting with the rest of the houses. I've talked to the man who owns 3 rentals right next to this, and he received feedback from the management company that an interested tenant walked away, and mentioned this as the reason. 

Who parks their RV like this, for over a month now with no sign of anything getting better? 

1. She is not allowed to park it on her grass section. The county has already gotten after her about that. She has to keep it on paved section. So now, she parks her car in the garage and drives across the grass to get out. The trailer was originally parked where the brown spot is in the lawn. 

2. We (myself and the man who owns the other 3) are thinking of offering to help pay to extend the fence out a bit so that this sits out of sight a little bit. 

3. I don't want to see me taking less in rent because of this. It is a duplex. Taking $150 off per month off each unit would be $3600/year. Is there a legal claim here?

Thanks