I know this is an old thread but emotional support animals are for a diagnosed mental health issue from a trained professional  in mental health not just an ordinary MD. 

Please call me if it's going to cost over $100 to diagnose or over $300 to repair.  

The experience I gained working in the home improvement field (residential and commercial) includes diagnosing, repair, estimating repair cost, networking with contractors etc.

Once you do that its a matter of getting someone who knows how to diagnose the system and fix it for you.

I was diagnosed with colon cancer over 5 years ago and if there was ever a slap in the face for the ages that day when my GI doctor told me I had cancer was it. 

Sometimes they are trying to actively screw you by relying on your lack of knowledge...... other times they are just straight up bad at their jobs and cant diagnose the actual issue, so just throw out repairs with the hope it may fix the issues.The flip side is that I've seen plenty of guys get second opinions from other companies and go with the cheapest one....only to find out that the more expensive guy was right and now you end up paying even more since the first "cheap guy" fix didn't do jack or even made the issue worse....so it can go both ways....

It also discourages tenants from reporting otherwise important maintenance items ("I'm not reporting this leaking sink drain that's the destroying the kitchen cabinets, they'll just blame it on me and try to charge me for it.").Finally, it's still quite possible that the oven has an intermittent problem, or a problem that was not accurately diagnosed by the technician (especially if it was a warranty or home warranty service call - they generally avoid making repairs at all costs). 

You will want a few foundation repair contractors to take a look at it to diagnose the cause.

Had your first tech been able to correctly diagnose the problem the second call could have been avoided. 

I could pay them $20-$40 for a service call first, and 90% of the time they could fix the issue or properly diagnose the issue.