Would it be wrong to use a finance-textbook approach e.g. recurring revenue divided by a rate of return? (Or rate_of_return minus rate_of_growth, using the Gord

Would it be wrong to use a finance-textbook approach e.g. recurring revenue divided by a rate of return? (Or rate_of_return minus rate_of_growth, using the Gordon model.) For example, if I get 1k/mo in ads, dividing it by (0.25 / 12) would result in a sale value of 48k. The rate of return must reflect of course the high risk of the investment (e.g. users may migrate to other app and revenue dwindles) and must also cover the costs of app maintenance (every major release of mobile app takes some maintenance in code, at least). I used 25%/year as example but I am not really sure if it is too low (or too high). Fact is, not many investments yield 25%/year.