How to deal with a neighbor's bad curb appeal
Form a homeowners association
If your existing neighborhood doesn’t have a homeowners association to impose aesthetics, you can try forming a HOA, or you can sell your home and move to a different neighborhood that already has a well-run HOA whose rules you like.
Neither option makes sense if you’re dealing with one bad neighbor. However, if bad curb appeal is a neighborhood-wide problem, one of these solutions might be the best way to preserve your home’s value over the long run.
Forming a HOA in a community where the developer didn’t put one in place means researching your locality’s rules about HOA formation and getting most of your community on board. You’ll need to hire an attorney to help set it up, elect neighbors to run it and agree with your neighbors about what rules the HOA can impose and enforce.
It would be easier to move to a community with a HOA in place, though you’ll pay the transaction costs of selling your home (at a discount, thanks to your bad neighbor), moving and getting a new mortgage.