Economically it's my experience as a web dev that overselling is the best way to get more resources because people always fall in the trap of sunk cost.
It is easy to get more funding by whatever resource you want when you got at least a bit. For example, lets say I want to refactor a whole codebase and I oversell it to my boss that it will take only 2 weeks when in fact it will take 3. Very few managers will in my experience say no to you getting an extra week due to the sunk cost trap when they may say no if you said 3 weeks at the beginning.
Of course, people may get disgruntled and unhappy with you if this happens to frequently but it is a powerful phsycological trick you may use when you really need it.
It is easy to get more funding by whatever resource you want when you got at least a bit. For example, lets say I want to refactor a whole codebase and I oversell it to my boss that it will take only 2 weeks when in fact it will take 3. Very few managers will in my experience say no to you getting an extra week due to the sunk cost trap when they may say no if you said 3 weeks at the beginning.
Of course, people may get disgruntled and unhappy with you if this happens to frequently but it is a powerful phsycological trick you may use when you really need it.