The nice thing about a mixed set is it's easy to start and easy to add to.
Be patient and be on the lookout for chips that you like and you can get for a fair price.
If you have one denom locked up, go to the next.
Keep doing that and you'll soon have a playable set.
You can always replace a denom if you find a chip that fits your set better later on.
I recommend you start with your workhorse chip which you need the most of (at the very least two racks). Try to get those two or three racks all at once and then add the other denoms.
I started mine with a rack of Aztar $25s then found the empress Joliet $5s, added the $1s, replaced the $1s with the LCOs that fit the set better and then got the hundos and the fracs.
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