Looking at the list of bonds you listed, many of them are long dated. In short, in a rate rising environment (it's not like rates can go much lower in the foreseeable future), these bond prices will drop in general in addition to any company specific events occurred to these names, so be prepared for some paper losses.
Just because a bond is rated highly by credit agencies like S&P or Moody's does not automatically mean their prices do not fluctuate. Yes, there is always a demand for highly rated bonds from pension funds, mutual funds, etc. because of their investment mandates. But I would suggest looking beyond credit ratings and yield, and look further into whether these bonds are secured/unsecured and if secured, by what. Keep in mind in recent financial crisis, prices of those CDOs/CLOs ended up plunging even though they were given AAA ratings by rating agencies because some were backed by housing properties that were over-valued and loans made to borrowers having difficulties to make repayments. Hence, these type of "bonds" have greater default risks and traded at huge discounts.
Most of them are also callable, so you may not enjoy the seemingly high yield till their maturity date.
Like others mentioned, buying bonds outright is usually a big ticket item. I would also suggest reviewing your cash liquidity and opportunity cost as oppose to investing in other asset classes and instruments.