Standardise the comparison unit first
Convert every option to one currency, the same course weeks, accommodation nights and participant count before comparing. Do not compare a 'weekly tuition' figure directly with a meal-included housing package or a different transfer scope.
Separate fixed, variable and unconfirmed costs
Fixed costs are normally written course or confirmed housing charges; variable costs can include meals, local transport and personal activity; unconfirmed items can include taxes, deposits, changes and service fees. Keeping all three separate prevents unquoted items disappearing as 'hidden costs'.
Work backwards from arrival day cash flow
List deposit, balance, visa/formality, flight, insurance, housing deposit and first-week living payment dates, currencies and refund terms. This can show that the problem is not total price but a concentrated payment week or greater refund risk.
Give contingency money a purpose
Keep a separately accessible amount for delayed housing, altered transport, necessary medical out-of-pocket cost or luggage problem, without treating it as part of a school quote. Discuss the amount from household capacity and trip risk rather than inventing one percentage.