I am confused as to why WPI was “pricey.” The following costs data sets were taken directly from respective university websites:
RPI $71,998 for 2018-2019 school year;
WPI $69,812 for 2019-20 school year (i.e., next year);
BU lists total estimated expenses as $69,668.
The WPI price actually includes a $5,000 automatic credit toward the cost of any seven week off campus research project at over 50 centers around the world.
Most students do not pay these list prices at any of these universities. You will do better to look for the best programs that match your requirements and at least run the Net Price Calculator (NPC) for those selected Universities. Costs are not irrelevant, but blanket statements may not reflect actual GROUP data.