Sure, a handy DIY'er could probably assemble a table and do a satisfactory job of installing bed cloth.!
I agree, and in my experience I would extend it to say a home-study mechanic can recover rails just fine, if they research properly beforehand, and if the table is not some fancy antique with odd fitments. I've done it myself once, and both bed and rails came out looking near perfect, no, they were perfect, to the best of my knowledge, which I agree is not the equal of King Cobra.
These are all problems that an expert knows how to fix the right way.!
Even the experts are human and can make rookie mistakes. I have seen it myself. After recovering all the cloth, including the rails, The Pro forgot to re-fill the bolt holes which he had just just dug the beeswax out of to loosen the slate bolts for leveling.
...and one rail was so rough, with a visible staple on top that caught on my shirt sleeves, a rail so bad that I bought another strip of Simonis at my expense, so he could re-do it when he returned to re-cover his re-cover job, and fill in the bolt holes like he should have the first time...
...but of course he never returned to fix his mistake. Nor did he return any of my attempted contacts. It's been two years, so I don't think he is interested in making good on his rookie mistakes any more.
Oh well, live and learn. And pay for the privilege.
Of course, I can't go raise hell at his shop because being a Pro Mechanic he works out of his pickup truck... and a storage building somewhere.
...and no, I am not talking about King Cobra, whose work I respect, and who has been a big help with the free advice he has given to all and sundry.