The IRS uses a two-part formula to determine the amount in an Offer in Compromise (OIC). The first portion uses the equity in assets you own. The second multiplies the income you have available each month after paying all allowable expenses by a factor of 48 or 60. As is clear from the equation, living expenses ultimately determine the outcome of many Offer in Compromise requests. The IRS will dig a bit deeper past the "standard" formula if it looks like you're going to qualify for an Offer in Compromise. The big thing to know if you're wondering how to get an Offer in Compromise approved is that the IRS will look at your declared expenses to see if they are what the agency would consider to be "reasonable" based on average living standards.
The IRS is even going to take a long view when evaluating how "reasonable" your expenses look. The IRS typically takes a five-year glance into the future to spot any expenses that will fall off during the lifespan of your OIC term. This often includes things like final payments on car loans. A taxpayer will need to be prepared to counter the claim that new funds will be freed up that can be used to pay down tax debt in the future. It's not typically possible to qualify for an IRS Offer in Compromise if the numbers work out so that you have more assets than the balance due. While there are exceptions, the writing on the wall for most people is that an IRS OIC probably isn't going to happen if you have more cash than you owe.