What gets expensive is if the plumber finds that the line isn't clogged from grease but from the line collapsing due to old age. 

As of March 2022, a new addendum was added to the loan  approval questionnaire as a result of the Surfside condominium collapse in 2021.

I tell everyone I know: if you call someone up for a job that costs less than a couple hundred bucks in materials and isn't some crazy oddball thing - patching damaged drywall from a leak is not an oddball thing; fixing a partially collapsed porch might be - and the guy can't give you a ballpark figure over the phone and says they have to come "see the job", they're going to try to milk you for every dime on the planet - because truly busy contractors that do lots of work know roundabout how long various jobs take, how much they charge for their labor, and about what the materials cost.

A bad enough bow, or an active one, can collapse the foundation on that side so I wouldn't take it lightly if you don't know what you are looking at. 

And/or you put something heavy over it you can cause the drainfield to collapse. 4- You flush wipes (even the flushable ones) and because those don't sink they float into the drain field, and,  again you're screwed, you'll have to replace the drainfield. 

High prices don't foretell the collapse of any market as long as there's a constant balance between buyer and seller.

What is a collapse?

If the deal collapses and I would lose everything, I'm out.

I get that lenders need to confirm there aren't any major health and safety issues after the Surfside, FL condo collapse in 2021. 

Recession or not, it all comes down to what your unit is doing, the country can economically collapse, but if you still have cash flow, it's not a recession for you.