Exterior Wood Screws
(May decide to buy the tan or red color version)
3"
https://smile.amazon.com/Phillips-II-Plus-Exterior-Screws/dp/B002UP9068/ref=sr_1_5?srs=3038474011&ie=UTF8&qid=1469895452&sr=8-5 $98 + $0 + $0 for 1750 (25lbs) (5.6 cents each) Grn (cannot find Tan)
https://smile.amazon.com/gp/product/B002UPCMPO/ref=s9_dcacsd_bhz_bw_c_x_6 $31.06 + $0 + $0 for 350 (8.9 cents each) Grn
2.5"
https://smile.amazon.com/25-2-1-Deck-Screws-TAN/dp/B002UPIXFC/ref=pd_sim_60_5?ie=UTF8&dpID=211y-8t2RaL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&psc=1&refRID=B8RSVF9867RDVVQKZWQN $98 + $0 + $0 for 2000 (25lbs) (4.9 cents each) Tan
https://smile.amazon.com/gp/product/B002UPCMQI/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 $31.06 + $0 + $0 for 400 (7.8 cents each)
1.25"
https://smile.amazon.com/25-7X1-1-Deck-Screws-TAN/dp/B003TPA5GC/ref=sr_1_53?srs=3038474011&ie=UTF8&qid=1469895225&sr=8-53 $98 + $0 + $0 for 5,250 (25lbs) (1.9 cents each) Tan
https://smile.amazon.com/5-15125-7x1-1-Tan-Exterior-Screws/dp/B006OMY5M2/ref=pd_sim_60_2?ie=UTF8&dpID=512%2B6VGm%2B8L&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&psc=1&refRID=MN61V4X8GETH8X3ZRSWJ $31.06 + $0 + $0 for 1125 (2.8 cents each)
3.5"
https://smile.amazon.com/9x3-1-TAN-Deck-Screws/dp/B002UP6Y58/ref=pd_day0_60_3?ie=UTF8&psc=1&refRID=G8BMWCZDZFT787NQP1ZR $9.54 for 55 screws
Info
2.5" wood screws 1lb is about 86 screws
3" wood screws 1lb is about 75 screws
Another possibility
(but not quite as good)...
2.5" pack of 350 $25.67
FastenMaster FMGD212-350
GuardDog Exterior Wood Screw, Tan, 2-1/2-Inch, 350-Pack
http://www.amazon.com/gp/product/B000VBBEI0?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00
3" pack of 350 $28.59
FastenMaster FMGD003-350
GuardDog Exterior Wood Screw, Tan, 3-Inch, 350-Pack
http://www.amazon.com/gp/product/B000VBBEI0?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00
3.5" pack of 350 $30.81
FastenMaster FMGD312-350
GuardDog Exterior Wood Screw, Tan, 3-1/2-Inch, 350-Pack
http://www.amazon.com/gp/product/B000VBBEI0?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00
3.5" pack of 75 $9.50
FastenMaster FMGD312-75
GuardDog Exterior Wood Screw, Tan, 3-1/2-Inch, 75-Pack
http://www.amazon.com/gp/product/B000VB9EMI?psc=1&redirect=true&ref_=oh_aui_detailpage_o03_s00