At first Jeff paid, $300/month x 12 months = $<<300*12=3600>>3,600/year
He paid $3,600/year x 3 years = $10,800 the firsts 3 years.
The final 2 years he paid $350/month x 12 months = $<<350*12=4200>>4,200/year
He paid $4,200/year x 2 years = $<<4200*2=8400>>8,400 the last 2 years.
He paid the owner $10,800 + $8,400 = $<<10800+8400=19200>>19,200 in total.
#### 19200