It has always been my understanding that trading seeds is permissable as long as seeds are labeled with the botanical name, not their common name. Also, packets of seed should not contain mixed seeds, such as wildflower mixtures. I have never been required to fill out any forms, but that may be my particular post office. I've had trades in South America, China, France, & several Canadian trades. The only time I had a problem was with the trade to France, the envelope was checked, but because they were labeled correctly, they were shipped on & arrived a bit late. Another trade took an extraordinary long time, almost a month, but I was very pleased with that one. Of course, it has been a few months since I swapped, so rules may have changed.

I received my trade from April and she was more than generous! I had only sent her a few bulbs, and she sent me huge clumps of the plants I had wanted! They are all now happily planted in my garden. :) She is a really kind and has excellent communication. I would highly recommend trading with her anytime! She also provides great advice. Thanks so much again!

@ Jeff - I'm glad you have decided to move forward with a professional. If this were a simple gut and reno that had everything IN TACT, it would be worth a DIY job. But your situation is beyond most people's skill level. And that INCLUDES some idiots with hammers that call themselves 'professionals'. Please vet all the people who apply for the job. A homeowner becomes the General Contractor (and all the legal weight that carries) when s/he hires subcontractors (like plumbers, carpenters, tile setters, etc). It is a rare talent that can handle framing (including jacking up as supports), furring out the walls to get them square, flat and plumb as well as a water proofing expert and a tile setter. Please be aware you want to work with a company or group of professionals who SPECIALIZE in bathrooms. They are going to be more expensive, but they *should have all the bases covered.

Does it really matter if the soil doesn't dry out. Can you smell it when the plastic is in place? If not since it is working leave it be. The soil should dry out as the ground around it drys out pulling the water from the soil under the plastic. Putting plastic sheeting is not any different than putting pavers, plastic ponds, etc on/in the ground. If you want you can replace with weed block. I have weed block with stones over it along the one side of my house to divert water and don't have weeds.