What is the best price to pay for satin sheets? Quality satin sheets are going to run you $120 to $300 for a full king-size set (bottom fitted sheet, top flat, and 2 pillowcases). Yes, very expensive. This is one area where you really get what you pay for. Higher prices mean not only better quality material, but also finer stitching of seams, etc.
Bargains are really only available when someone is closing out a pattern or color. Sometimes a company will offer an annual sale where they sell their canceled orders, but selection is very limited.
Anything less than $120, particularly for a full set (top and bottom sheets plus pillowcases), is going to be a cheap department store quality. Most likely it will be a knit material, even if not described that way.
Most reputable satin sheet stores do not stock pre-made sheets - they keep the bolts of material and make sets when orders arrive. This means it may take 1 to 4 weeks between you placing an order and it actually shipping. Be wary of ready-to-ship stores, they are quite possibly offering knit instead of woven fabrics.
Satin sheets are available in any size, and of course you can get satin waterbed sheets.
Because real satin is expensive, many stores sell top and fitted sheets separately. Be careful to order full sets (fitted, flat, plus pillow-cases). I recommend buying at least 2 sets of the same color so you always have a matched set, even if you damage part of one. Since my husband and I have 4 pillows on our bed, we bought lots of extra pillowcases.
Take care to look for deep pocket cut fitted sheets if you have a pillow-top bed; woven satin doesn't stretch much and nothing is worse than a sheet that keeps pulling off the bed!