Those handmade real estate signs at intersections

[Stephen Shelton]

In my area it's not uncommon to find little signs at intersections looking to either buy ugly homes or to sell a house to an investor to flip.  These hand-written signs are there one day, and gone the next.

What are these? My educated guess is that they are done by local house wholesalers hoping to make a profit, but are they something else? A scam perhaps? Call up and I have to attend some scammy seminar first? Anyone here ever acquire a home through something like this?

I find them tempting because if it is just a legitimate wholesaler out selling homes I never even knew existed then it could be a great connection to have, but if these have a reputation of being scams then I'd rather stay away.