Here in New Jersey we have two standard VERIZON lines, each with its
own number, for our residence. We purchased what we thought was a
standard servive contract that would cover inside and outside our
residence.
The first time we ran into a line problem, VERIZON said it occurred
within our residence and hence was not covered by the warranty
contract.  They added that they do NOT provide internal repairs nor is
such a service contract available.

They gave us the name of a private unaffiliated repair service.  We
took a bit of a beating on the cost for repairing the line, well over
$200 dollars.

Today the line went down again. We had no choice but to call the
private service (there was a splice short).  Once again we had to pay
over $200 for about 90 minutes of work.

I turned to google to see if any company offered such a service
warranty.  I found nothing. Perhaps one of your experts can dig one
up.

Verizon's standard service contract only covers availability of their
network, which effectively ends at a demarcation point located either
on the outside of your home, or immediately inside the home (ie. where
the phone line enters the home). Verizon also offers optional wire and
jack maintenance plans for their New Jersey customers, for prices
ranging from US$3.45/month to US$3.95/month . If you have one of these
plans, Verizon will diagnose and repair problems without incurring
per-incident charges. They exclude what they call "pre-existing
conditions and problems", meaning that you must be signed up with the
plan before a problem manifests itself.

You can find information about these plans at:

http://www22.verizon.com/foryourhome/SAS/res_fam_wiremaint.asp

Please note that it is necessary to have one of these plans for EACH
individual phone line service, so in your case that is two lines. at
$3.45 for the basic inside wire maintenance plan, that works out to
$82.80 per year for coverage. You can also add a Telephone Protection
plan for an additional $3.95/month/line, but note that you must
register each phone and caller-ID device in order for it to be
covered.

These plans are the lowest cost maintenance plans available to you
given the low number of lines involved. Telecommunications system
integrators will often provide maintenance contracts to their
commercial clients, but usually only as part of an installation and
design contract for a larger telecom system (such as installing a PBX
into a new office building).