Two very different things.
Although you might think you earn enough money to get a mortgage that doesn't mean the bank agrees.
Bonuses, commissions, self-employed income, and rent are viewed differently at banks than in the real world. This is because a mortgage is for 30 years so they want to make sure your income source continues to be reliable, and if it's not or is new then it's unlikely this will be factored into the income side of the bank's equation for your application.
Equity - don't get confused, this isn't free money, it is a loan secured against an asset, and the amount of "useable equity" depends on what that asset is used for (home or investment property, new build or not) and who is giving out the money.
A lot of things to expand on and that is why Ant & I did this podcast.