Yes, use the acid tests kits for any jewelry you find, just to be sure. Sometimes "Silver" can actually be white Gold or plated 10K Gold or if you can't tell the difference Platinum.
I would recommend going to some high end antique shops and auction houses so you get a feel for what truly rare and/or expensive antiques and collectibles look like. For the most part, you are not going to find candle holders & vases & collectibles worth more then $100. Most things that are really valuable will actually stand out even to the untrained eye. Yes I know there is always some kind of goofy stuff that is not high quality but is hugely collectible and valuable, I just mean to say, for the most part, you don't need to run to an appraiser for every unique thing found in a unit.
Novice test for getting more information: Answer yes to these questions, seek out an expert.
1. Does it look valuable?
2. Does it appear to be in mint, like new, or near perfect condition?
3. Does it appear to be made with high standards or specialized techniques?
4. Is it the first time you have ever seen something like this?
5. Do you and everybody who looks at it go "WOW"!?
Don't know how things are in Australia but TV shows here in the US, especially American Pickers, have turned basically junk into valuable collectibles so you need to educate yourself into what collectibles are popular in your region/country.