@soily, The way you framed a great question, it seems you want to use the full $30K windfall for a down payment, but you have a home with $80K-ish mortgage at a relatively high 4.4%. So assuming you have some equity already; and to really get out of debt for life, you may be best off by not buying the bigger house for now. Instead, kill the student loans TODAY... PLUS pay down $23K of current mortgage debt... PLUS save hard to move up once you've paid off the current place. Then you'll have a smaller future mortgage and more cash flow from zero other debts to hammer the new mortgage that way. With feeling, you do this as in every shekel you can scrounge or dig out of the sofa cushion goes to kill that debt! One caveat to keep in mind is mortgage originators aren't dumb to borrowers trying to break the debt shackles so they will offer best rates & fees to 1st mortgages big enough that you won't pay them off too quickly (as a lot of their compensation is on how well their loan originations pay long-term so the mortgage backed securities continue to pay coupons to people who invest so their money pays them which is where you want to be ASAFP). They actually call people who pay mortgages early "dead beats"! It's the dark side of the "American dream of home ownership".
Or another way to look at this if you can't wait to pay off the current place, if you are trying to avoid PMI buying a bigger house, why do you want to burden yourself with a bigger house PLUS student loan debt around your neck? It just sells your freedom back to 2 banks again. How quickly can you pay back the $7K with free cash flow THEN throw an entire $30K or more to get where you want to be after you really get after it? Save hard and WIN!