Where to find more leads? Posting little signs?

[Eran Greenburg]

Im sure weve all seen signs around like "we buy houses fast, cash" or "we buy ugly houses," preferably the small cheap throwaway signs on freeway off-ramps etc 

How well does this work?

What are some other lesser know yet effective methods or capturing leads before they go to the MLS/auction? Sure contracting FSBO, or mailers (how to target), but seems like poor ROI