Which is better?

[Kerry M.]

Trailer in a college town for sale for $10,000. Lot rent is $250-315, depending on water/sewage/trash/taxes. Condition well cared for, not moved; old but no repairs needed. 2 bedroom, 14 by 70. Renting one room in a shared apartment runs $4-5,000 per school year for that area. Room and board at the college is $8,000/school year.

Question: given the need to pay for room for (my) student attending college or purchase of trailer, how do I tell at what point one option is financially better than the other?

Thanks!