I have a wife who works in one of the seminaries in an administrative capacity here in Israel. The costs of the seminaries (and yeshivos) are high and growing all the time. Additionally, the weak dollar to shekel rate and the vast majority of the expenses (salaries, electricity, food, etc.) being in shekels leads to the rising costs (in dollars) of the year in Israel.
The seminaries differ in cost structure from the yeshivos in one large way financially – they offer fewer meals than the guys get in yeshiva.
The seminary has to have a larger staff than a typical girl’s school in the US – girls are away from home for the first time (for a lot of them) with a huge time difference and great distance between them and their families. This leads to madrichot and other staff to help them deal with issues.
This is additional to any costs of the teachers that there might be.
The dormitories need to be kept up, wear and tear. There is an em bayit who is employed to deal with after hours issues.
There are tiyulim. When you wrap all of this up – it does cost a lot.
I do not know of the US grants or loans or other programs – but MASA is sponsored by the Jewish Agency as a program for that year in Israel and they do offer grants.