Just starting out I would start with a smaller area, possibly farther away from city center or pick a specific neighborhood or small area and pound it with bandit signs, letters and maybe even door knockers!

I buy 90 Pound card stock from Amazon and then have Office Max cut it into postcard size and it is really inexpensive.I usually double or triple the money I've spent on my mailings.

@Jonathan Holmes, @Joe Davalos and @Michael Ablan There are a number of sites where you can direct people to get off mailing lists.The FTC has an informational site about all sorts of unwanted contact: https://www.consumer.ftc.gov/articles/0262-stopping-unsolicited-mail-phone-calls-and-emailBut the place to go for opting out of mail is The Direct Marketing Association: http://www.directmail.com/mail_preference/Most professional and ethical list compilers will run their lists the the DMA suppression each month as part of the standard list hygiene.

This way you can go down to 150.000 pounds prices. 

One of the concepts that is brought up often is “what happens when there are no more unwanted animals?”

In the meantime I know how you can lose 50 pounds by eating more than you do now and not exercising....I’ll tell you for $1900 or you can look up tapeworms on Google.

Texas is full of fantastic "unwanted" rural land deals.

I charge a minimum $25 per month per animal (small dog under 20 pounds or a cat) and up to $100 a month for a large animal.

Sure, you could rent your property ST on craigslist and facebook to try to get around this... but running successful STR business pretty much requires playing nice with the 300 pound platform gorillas.

Right before the hunting season starts, flood the pound.