I have been searching ebay for a cheap air impact wrench for a while now, and then I noticed an impact wrench/ impact ratchet combo is for sale at the Home Depot ($20). Here is the link:
Husky 1/2 in. Impact Wrench and 3/8 in. Ratchet Wrench Combo-HDK4430-4110 - The Home Depot

My local store has 5-10 of them in stock, and perhaps your store is the same. But it doesn't appear to be on sale on line.

I haven't used mine yet so I have no idea how well they work, but I have to assume they are no worse quality than what you get at Harbor Freight, where their cheapest is twice the price.

At the very least, please nobody pay more than $20 for this combo in ebay any time soon.

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1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).

I bought this set and haven't used it, figured it's a throw away item though the cheapie impacts are strong enough for moderate use, okay for the DIY mechanic.

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Current: 1975 450SEL, 83 300D, 88 Yugo GVX, 90 300D OM603 swap, 91 F150 4.6 4v swap, 93 190E Sportline LE 3.0L M104 swap, 93 190E Sportline LE Megasquirt, 03 Sprinter, 06 E500 4Matic wagon.