Scenarios:

‘I have bought privately before and am very wary’
You need to explore your options very carefully. A FREE TRIAL is what you need.

‘I think private hearing aids and batteries cost a fortune?’
Not necessarily. Have a look at the audiology companies online that list complete product price lists.
For batteries etc, you should buy them on an accessory website: such as www.hearingaidparts.co.uk

‘I have or had a particular make (of hearing aid) in mind’
Keep an open mind. In my experience, consumers who ask for a specific make have usually been unduly influenced by a less-than-independent opinion and over-the-top marketing. Many audiology retailer practices are now owned by individual manufacturers, and so they do not offer a truly Independent opinion. Which magazine’s articles in 2014 / 2016 / 2018 found that independent practices were the most likely to give you the best overall service.