How much to replace my water main from my meter to my house?

Here at the twin plumbers we receive a variety of plumbing email inquires on a daily basis,everything from faucet repairs to sewers to what we received yesterday from a Lorin. We sure love to educate our customers and provide the most honest information there is in the plumbing business. Here is her email:

Hello twin plumbers,my name is Lorin~ 
I have diagnosed a leak from the water meter to my house. I turned off the main water, then checked the meter–it was still going. 1.5 hours later with the main water still off I had used 30 gallons. 

Now the real question…how much should it cost to do the repair. ? 
I will need a new water line from the meter to the house. There are no “puddles” that I can see in the lawn to tell me where the leak is. 

Distance: 20 yards 

Nothing is in the way of replacing the line–ie. no driveway, sidewalk, or anything, just grass. 

The water shut off valve for the house is on an inside wall, about 5 feet from the outside wall so at max the water line will run a short distance in the wall or under the cement slab. I assume it is highly unlikely that the leak is in that area since I see no water in the house, although presumably it could be under the cement slab (the 5 feet it may run) and just not coming into the house. 

Price quotes that I have gotten: 

1. 5800$ plus a 20 year warranty (obviously ridiculous, they were shady salesman-like people who after talking to others seem to give high quotes hoping that someone will bite). 

2. 1,900 for line from water meter to house, no work on the 5 feet into the house. Extra “several hundred” dollars if they have to redo the piping inside the house. 

3. 2900 for complete redo–from water meter to main water shutoff in house (ie. includes the portion in the house), but they said it will leave open dry wall and maybe some cement that is torn up, for which I will be responsible for redoing. Offered 2500 for just the line from the water meter to the house (ie. no inside work) 

I can’t believe the amount of differences in the quotes. My temptation is to go with the 1900 quote but I have been burned by plumbers who don’t do the right thing, I love what you guys have expressed in other informational pieces, your advice and bid is much appreciated. 
Thank you, Lorin 

As you can see the prices very from one plumber to another, and Lorin is obviously very confused and sadly has had bad experiences with plumbers in the past. The bottom line, she has 20 yards which is 60 feet of trenching and 60 feet of pipe to install. It sounds like its a pretty simple straight forward installation with exception of the length. Here is a short video that can answer the question on prices for a water main replacement.