Solution:
Total cost of van = market cost of van + 6% sales tax on market cost + document verification fees
6% sales tax on market cost = market cost x 0.06 = 26857 x 0.06 = 1611.42
Total cost of van = 26857 + 1611.42 + 250 = 28,718.42
20% of total cost of van = 5843.684
Remaining amount = Total cost of van - initial financing = 22,974.74 dollars
Hence 22,974.74 dollars is the total amount that Williams family is financing.