If she sells, presumably she will have spent some of that money or maybe put it into an IRA by the time it is time to fill out the FAFSA or CSS. They only ask how much cash you have TODAY, not what you had last week. If she does not spend it or needs to save it then she will have 75k in cash which is the same as having 75k equity in a rental.
Roughly 75k in assets will cost about $4237 in aid a year after the base allowance is used up.
Net income of 25k will cost about $5000 a year in aid ($income is tapped at 20-25% although it can vary in formulas and that is after the allowance.)
In the year she sells how much is income will depend on her profits. For this the $75k number is not important because according to the OP if I understand correctly, 75k is her equity not what the entire property is worth, presumably that is more and profit will depend on the purchase price and the selling price after deducting expenses. So only OP knows what her potential profit would be, we do not have that information. Further, the capital gain may be significantly higher if there is depreciation recapture