Bottle ownership IS a big deal for the gas suppliers. As are financial LOSSES due to theft of co owned bottles.
Just about any gas supplier has some stories about a dishonest (end user)person selling some other un-suspecting end user person a set of leased bottles (often times near the end of the lease period, when the lease payment is due). When the honest purchaser takes (what he thinks are his) bottles in for a refill, the Co says thanks for returning our property, AND you OWE us an additional lease payment.
The best cure for bad behavior on the part of gas suppliers is COMPETITION. Now, with 3 gas suppliers competing for business in this area (and a change in ownership of one TRADITIONALLY less than user friendly suppliers), privately owned cylinders are being looked upon with more favor.
Yes, if a cyl. DOES in fact fail the re-cert process, then the testing outfit should follow the FEDERAL regs, and mark the cyl. to prevent further use. And the testing does include a visual inspection. However, I have hear stories of company test facilities marking customer owned cyls. as FAILED without proper inspection (simply to remove them from service, and force welders into Co. LEASED cyls).
Any reputable cyl. testing outfit should provide you with a WRITTEN record of the cyl test results (by cyl S/N), PASS OR FAIL and WHY. If you have questions as to WHY a cyl. failed, get the WRITTEN documentation at the time you pick up the cyls. In fact, get the DOCs regardless PASS or FAIL. In the worst case, you then have something in writing in case of needing to file a law suit. If a tester has scrapped one of your cyls, AND is UNABLE or UNWILLING to provide written documentation as to the REASON for test failure or scrapping, you may have the basis for a claim against the tester.
My opinion is that leasing cyls. is simply BUYING cyls. for someone else. Unless gas cyls. are ABUSED (left sitting in wet, salty mud for years & badly pitted & rusted, dropped/dented, or other ), they should last for MUCH longer than the lease period. I personally have cyls. (which still pass cert.) that are more than 50 years old, and I expect to use them for another 20 years. Most cyl. leases are for 10 or 20 years.
A little research is in order whenever you are offered cyls. for sale by an unknown individual. You might save yourself some cash and law enforcement headaches.
If you have cyls. which you clearly own, you are responsible for getting them cert'ed (as required by date) prior to getting them re-filled. Most gas providers have their own facilities for this. However, these (in-house) facilities may not have YOUR best interests in mind when doing the cyl. testing & inspection. Most larger cities will have someone else who does testing of other HP gas bottles (say SCUBA tanks). Do some research & asking around. Then use the independent test outfit to do the re-certification & inspection. Then you can take your bottles to a gas supplier for a fill.
Many companies will also treat customers with accounts entirely differently than the person walking in off the street. Opening an account and buying some gas may help.
If you have a chance to buy a set of cyls from an individual, check the name on the cyl neck ring. If the name matches a local supplier, make a phone call & ask if the size cyls being offered are leased or sold by the co PRIOR to cyl purchase. If the co. is not local or nationwide, then check the most recent stamped cert date. Factor into your offering price for the cyls the cost of re-certification, and the possibility of cert failure. A purchased cyl. which fails cert is just an EXPENSIVE piece of scrap metal, which may be hard to dispose of.
Note that there are different specific regs dealing with HP gas cyls, acetylene cyls, propane/LPG cyls, etc. Do some research, become informed, and save yourself LOTS of headaches.