Several clients I have dealt with wanted catalogues but the longer view was that they may become full ecommerce sites. In that case you simply go for one of the better carts and turn of the purchase options to create a catalogue.
Which cart will depend on number of products and type of attributes required. Virtuemart has always been popular but it has declined due to lack of flexibility in Version 2. Hikashop is also very good but often requires CSS changes to bring in line with template styles. I haven't used any others except RedShop and I had no end of problems with that product a couple of years back.
If there will never be an option to buy then I would probably create a content override for Joomla and make each product an article within categories. Alternatively you could use one of the various page-builder extensions to generate a template for product articles. This would give you a very flexible means of creating templated product pages.
Hope this helps
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