I had a furnace service guy that lived a few blocks away and we were alway scheduled late in the day because of this. He showed way late once, I gave him my cell number and asked him to call me if that was going to be the case.
A few years layer we ran out of oil in a cold snap, and he came at 3 am in 18" of unplowed snow to fill the tank and bleed the system. I got a bill for the oil, but not emergency service.

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95 E300D gave away
77 300D, 227k, station car
83 300CD 370k, body gone away to the rust gods, engine is in a Yota pickup, going strong
89 190E 2.6- 335k, no more
79 VW FI Bus- 154k summer driver
59 VW Beetle ragtop- 175k
12 VW Jetta- 250k
74 MG Midget-78k