Price 0:- or free

can they be made so that if you put an item at a price of 0:- that they then say free instead of 0:-?

0 :- is usually a user error I see often by the merchant forgetting to set price for newly added items. Calling them Free could be changing the legal term what is referring to the items on sale and not what the merchant has in mind. Can it be done, yes? Is there a readymade feature or modification? No. Can somone do this for you? You would have to put the word out.

There is a post that maybe can help you:
https://www.litecart.net/en/forums/2/general-discussions/18912/hide-price-when-0-and-replace-with-contact-form
Eventually I can do it

I use this one, it appears in the product and on the home page

@javierromerojr work this on 2.5.5?

Yes

It seems that perhaps changing the zero to a negative value might alleviate the problem Tim mentioned of forgetting to enter a price, as well as it needs to be zero for price attributes to take effect (I think, I'm a LC newbie still)

It doesn't have to be exactly 0 to appear "free". You can also change the variable and set the price in the example: product price = 10 and it will show "free".
Remember: if you add the example: product price = 10, the cart will show you its real price, which would be 10.
    This is useful in case you forget to enter the price and it does not appear free