All of these things can impact how much you qualify for in a negative way. Some items may cause more paperwork to be needed to complete the loan process. Some things might make the amount you once qualified for much less than you first were told.
One example of a big no no: going from salaried to a self employed individual can literally make it not possible to obtain a loan any longer. Self employed individuals need to demonstrate at least a one year history of self employment for the income to be usable for qualifying. So if you quit your job and start a business it could possibly be at least one year before you can realistically start house hunting again.
Long story short if any of this seems like a possibility, do yourself a favor and contact your loan officer to figure out a way around it or if it already happened figure out a way to address the problem it may have caused.
We are always here to help. Contact us anytime.
*source - lighter side of real estate