I've UPS'ed my tools and parts to my hotel numerous times for work recently. Include "Attn: Hold for Guest John Smith" in the address.

Time it to arrive a day or so before so you can check the tracking and then call the front desk to confirm it is there and remind them when you're arriving.

If you can generate a return label and send it along for the trip back, do that. Include a mostly used up roll of packing tape so you can pack it back up to ship home. The hotel will probably not have a regular UPS pickup but you can request a pickup or just locate the nearest UPS store or whatever.

I also pack only 3-4 days of clothes and just make sure the hotel has an in-house laundrymat - hopefully a free one.

I hate traveling for work but I try to make the best of it.