https://www.youtube.com/watch?v=3H_EQBBru38

Doesn't look all that bad to me. The repairs on the sail panels because foam on the underside of the sail panel will hold water and cause rust under the vinyl. Someone welded the holes up for the side marker lights to give it the Euro 914 look. I would guess holes in rear panel were from when a after market Porsche reflector was installed sometime during its past ownership.

The shop person seems sort of clueless about the common issues on a 914.
Most guys who do know 914's would be ecstatic about the lack of rust.

Is that your car? Didnt bother to video the hell hole?

I'd be dancing a jig The biggest worry is what might be hiding behind those threshold patches and, of course, the hell hole.

That is a very clean tub to begin with. All very minor issues and issues one would expect on a 914. Take at look in the engine compartment below where the battery goes, the well know "hell hole". Check that for rust. Check your suspension mounting points, check the rear portion fo the the trunk where it meets the taillight panel, check the inside bottom of the firewall where it joins the interior floor. But overall, I think anyone would be happy to start a build with that tub.