I wouldn't push the Issue.
Your father would know that getting a bigger house Is a huge financial commitment and that If getting a bigger house didn't work out,that It would make life even worse for the whole 5 of you.
They have to make a mortgage payment commitment of up to 30 years, how will they keep it up after you move out?
Perhaps you could enter into a contract as part of an investment partnership to reassure the parents that the mortgage would be covered, in which you continue to contribute to mortage payments even after moving out, knowing you could inherit the house or get a payoff in the distant future.
your parents probably have no money saved for a down payment and there are no 100% loans to buy houses
he probably doesn't have a good credit standing as well and would not qualify for a mortgage
if you, your brother and sister make $1398 between you maybe you need to consider moving out to an apartment of your own
Investigate options for you family through Habitat for Humanity.
We currently live in a 2 bedroom apartment. Family of 5. I have a monthly income of $449. My sister has a monthly income of $500 and my brother of $449 we have the same job. Any who this apartment is incredibly small. We can barely fit a bunk bed and a regular twin bed in our room (the kids room where my siblings and i sleep). And don't forget this neighborhood is the worst. I'm talking about druggies everywhere and street dogs and cats. There is no one from school that even lives around here. I know we can afford a house because I've done the math. I'm even willing to give my whole check up. My mom really wants to but my dad always says we can't afford it. I don't even want a huge house. A 3 bed would be enough honestly.
