On off times, I sometimes take a day or two just wandering through thrift shops and yard sales. I found a huge bag of fake fruit for $3.00. (Fake Fruit retails at about $2.50 a piece). One day at Good Will I found 2 metal goblets. They are perfect for rehearsal, as glass tends to break, but we have also used them in performances. I have a collection of metal trays that get used often. I've also found things at 99 cent stores. They have a lot of odd assortments. Silk flowers, though not the prettiests ones, can be gotten there. (They retail for around $3.50...when you need a bunch, that adds up.)
Once you've exhausted the yard sales, thrift shops and 99 cent stores, there may still be some specialty items you still need. After hunting down pictures of what you need either on line or from library books (trust me, the internet does not actully have everything, it's gotten to the point were there is so much out there, you can't narrow it down to the real specific.) craft stores are usually my next stop. Colored clays like Sculpy and Fimo are great for makeing some interesting peices. Once I had a situation were we needed chili. The producer got canned chili, but the smell we nasty! Since the actor did not actually eat the chili, I was able to make a nice bowls of beans and ground meat out of clay. No one knew the difference. One time I needed a knife hidden in a cross...I used a butter knife cooked inside a sculpy cross. That took a little more time than the chili, but it worked out in the end. Using materials from the craft shops, I was able to recreate renaissance style fans. Think outside the box. That green foamy stuff that is used for plants; paint it gold and you have a nice gold brick.
For really specialize items, you may need to spend a bit more money. I have picked up a few things inexpensively at antique shops, smoke shop and even at mall stores. (I got a nice "business card holder", which was oddly the size of a cigarette case, at Hot Topics.) When all else fails, there is alway ebay. Just make sure your items will arrive on time.
Instant iced tea makes the perfect color for many beverages including tea. Then you don't have to worry about mixing the food coloring to the right amount. Of course food coloring in water works for many situations as well.
If you need documents, letters, or other papers, be sure they are not blank. I usally put song lyrics or some thing silly to fill the space. If you put the actor's lines on the paper, make sure they have them memorized as well, because you never know if something is going to spill or the prop gets torn, and then they will look silly because they no longer have the lines in front of them. If you need something period, you can use parchment colored paper, though I'm told that is not really authentic. You can always use tea to color your paper.
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