Newbie question - equipment with good resale value

What are some brands and models that have a liquid market in them?
I have a system (a cdp, integrated and two speakers) that I am somewhat happy with. At the same time, I would like to try turntables and tube amps. However, I don't want to make large investments. Rather, I would like to buy used equipment and sell it if I don't like it. Yes, I made some trips to the local audio stores but they have limited number of choices, they are are all expensive and are all similar to each other.
What are some brands of turn tables, integrated or separate tube amps that you would recommend I can buy and try without loosing too much in the transaction?

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Good question.

I have been playing the A'gon buy and try game now for a few years. First, you will need a membership to tbe A'gon Bluebook. The price graphs there will answer the question you raise. I tend to avoid items with minimal transction activity.
Almarg has good advice and Tvad and Tzh21y list some names. The only sure-fire way to "know" the history of prices and get a feeling for where items trade is to get a subscription to the Audiogon BlueBook, to understand that it only works for relatively liquidly-traded items, and to understand that it does not work.

The other way to get good equipment at prices which will not cause you to lose too much money if and when you sell it is to buy what I would call "soon to be but not yet classic" gear at 20-30cts on the original dollar. I have bought some 20-30yr old equipment at that kind of prices, and all the well-regarded pieces I have bought have been real prizes. Sometimes really excellent equipment just loses its fan appeal, drifts down to that kind of price after a decade or two, and then it represents absolutely fantastic value for money.
Definitely good advice above. Buy used from reputable sellers and you will not loose much if anything on smart investments that way. Two more omissions from above:

Cary and Teres