A good account of land prices in Vegas in the '40s and '50s is found in our book Fly on the Wall -- Recollections of Las Vegas' Good Old Bad Old Days by the late Dick Odessky.
In his chapter "Subdividing The Valley," Dick reported that Thomas Hull, who built the El Rancho Vegas at the corner of Highway 91 and San Francisco Avenue (now the Las Vegas Strip and Sahara Avenue), bought the land for his motor inn for $100 an acre. (Strip frontage today is going for more like $20 million per.)
At the time, locals believed that Hull had overpaid for the parcel. In fact, a real-estate speculator, Ted Griss, decided to buy up the property to the south and west of Hull's hotel site and paid only $1 an acre for 5,000 surrounding acres. Today, this is the land occupied by Circus Circus, Slots A Fun, Westward Ho, and the Stardust, along with all the topless bars and porn shops, limo and bus yards, bars, and miscellaneous stores and warehouses strung along Industrial Road from Sahara Avenue down to the back of the Stardust.
By the way, Griss also owned another 10,000 acres of good-for-nothing desert 10 miles southeast of his Highway 91 property, which he accepted as the payoff for a $4,000 gin-rummy gambling debt. Today, this is the Warm Springs Ranch development, filled with 25,000 houses.
Meanwhile, Dick, who worked at the Las Vegas Sun as a cub reporter in the early 1950s, had the opportunity to invest in more worthless scrub in Paradise Valley, "at the convergence of two dusty trails that later became the intersection of Flamingo and Paradise roads" -- perhaps the same place where this question submitter could have invested. Norm White, one of the Sun's ad salesmen, started buying up large lots in the area for a song. White offered to cut Odessky in on some of the deals, wanting him to invest $5 per week. Dick opted for his weekly haircut instead.
White did manage to interest Hank Greenspun, publisher of the Las Vegas Sun, in "an ocean of greasewood and mesquite" even farther out than his own slice of coyote habitat -- "toward an area that the owner was calling, half as a sales pitch and half in sarcasm, Green Valley." Greenspun wound up buying it all and today, Green Valley is more extensive than Warm Springs Ranch and Paradise Valley put together.
Finally, Dick writes about the "collection of small parcels owned by World War II veterans who’d been allowed to buy federal land in Nevada for $5 per acre (granted on a lottery basis) in five-acre parcels. Southern Nevada home developers turned their real estate agents loose, offering to buy the parcels for $125 each. Thousands of them sold, taking their $100 profit and running.
Two men Dick knew, who’d been stationed in Nevada during the war, were awarded five acres each at the intersection of West Charleston and Decatur. Much later, they came to Las Vegas to visit their land, which turned out to be adjacent lots on the only undeveloped corner of the busy intersection -- "which they sold immediately for a king’s ransom."
It would be nice to be able to go back to that time and buy up Las Vegas real estate at $25 for five acres, wouldn’t it?