The reason most chicken rearing operations close is because chickens are now raised by farmers who are under contract to large poultry processors like Tyson etc. As Government regulations multiply and record keeping becomes more odious the true owners of the birds (Tyson, etc) are forced to change the terms of the contracts under which their chickens are raised.
Many of the chicken farmers are close to retirement or else their physical plant is outdated yet the processor owner (Tyson) must insist on the farmer making new and sometimes expensive investments and changes to their farm plant. Unless the farmer and his descendants are assured of a continuing supply of cheep, steady, and conscience farm labor (usually family members) the farmer can not (nor can the bank) justify investing in a concern that for whatever reason is on a downward glide path.
The chicken litter in commercial chicken houses is little different from the chicken litter produced by back yard chicken keepers who use the deep litter method. I would put out local adds to the beef, hay, and row crop farmers advertising chicken litter for sale. Check with the local County Agent or Auburn University about the value of your chicken litter. It is an amazing fertilizer for beef pastures, grass lands, (hay) or sometimes corn and soybean farmers, but it is a terrible fertilizer for making precise amendments to soil fertility and if the land or the crops on the land don't need what is in the litter, to the farmer it is worthless or worst.
There is a farm implement called a chicken litter aerator that works much like a PTO driven rototiller or frail mower. Its purpose is to loosen the litter or thatch. Then a farm tractor with a rear mounted dozer blade scrapes the dethatched litter into neat wind-rows. Next a farm tractor with a front end loader is employed to scoop up and load the win-rowed litter on the farmer's trucks.
Know how many cubic yards the front end loader bucket holds, this is the basis for how much chicken litter your friend is selling. Weighing every load is a fools errand because the moisture content changes by the minute. A starting point for value at X% moisture is or was $30 a ton. This price is excluding trucking costs and is figured from the cost of a like amount of synthetic fertilizer. I have seen shysters selling or attempting to sell chicken manure on Craigslist @ $15 for a 2 pound coffee can full.
http://www.caes.uga.edu/commodities/fieldcrops/forages/documents/GC9506.pdf
I don't know how big your friend's chicken houses are but most of them are in the 400 X 40 feet range or about 16,000 square feet. That is a good starting point when estimating the amount of litter your friend has on hand.
The greatest and most constant threat in old chicken litter is a beetle called a "Darkling" beetle that for all the world looks like a mealy worm beetle. The same mealy worm sold in pet food stores for bird food and chicken treats. However under a heavy thatch of litter this beetle (which feeds on waste chicken feed as well as plain old chicken waste) can multiply to astronomical numbers that acts as a vector for every chicken disease and internal poultry parasite known to man. Commercial chicken houses are usually treated to prevent this beetle from becoming a problem but who knows how long that has been? Tis best if the old litter is moved elsewhere.
