Tenants complain about sewer smell. $8k rehab?

[Eric Parnell]

Hey fellow landlords,

I've got an older property that the tenant has complained about a toilet backing up and smell coming from the toilet/and or pipes. I had a plumber out there and they scoped it and said the pipe under the driveway is clogged and he can replace it for $8k. I had another guy come scope it for a second opinion and he said he jetted it, got through any major blockage and it should be fine. Well now months later, the toilets are not backing up but the tenant is still complaining about the smell. I'm out of state and don't know how bad this really is. 

Does anyone have experience with this? Do you think there could be any other solutions than replacing the main line?