After exchanging gifts a number of times with a Neighbour and receiving a large quantity of 'Bottles' I neither needed nor wanted, I realised a post on the subject might be in order.
I have written about this on my HarvestMoonForever site in a post comparing the Gift Options in various Facebook Games but perhaps Farmville needs a post of its own. In many of the games, one can accept a Gift and then immediately send a Gift back to the Neighbour who sent the first gift by pressing a button. Farmville provides this Option BUT the only Gift you are allowed to send back in these circumstances is the Item that you received.
When Neighbours do not communicate in any manner other than through Farmville Gifts, it is difficult to know if the Item that is being sent to you repeatedly is one that the Neighbour actually needs or if you both have become embroiled in an automatic 'give and take' business, essentially WASTING your allotment of Free Gifts for that individual by hitting the automatic Gift Return.
Rather annoyingly, Farmville makes its own Gift Suggestions. These pop up on your screen periodically, interrupting your important FARMING to suggest that you send a Mystery Gift to a Neighbour who has been 'working hard lately' (or words to that effect). Recently, Farmville has created a new Gem Collection and whenever you find a common Gem, suggests that you 'share' it with your Friends and Neighbours. This would be fine if the 'sharing' were posted in the Game Feed (and/or Wall) in the usual fashion, but instead, you are taken to a page that is similar to the Free Gift Menu where you are asked to target specific Neighbours and Friends for receipt of this Gem.
The problem here is that common gems tend to be those that EVERY ONE has found on his/her own Farm. You therefore are wasting your Gift allotment by sending a Gem that players probably have in their own collections.
A player who has been involved with Farmville for a long time informed me that a Gift can be sent every three hours to any designated player. In other words, if you are connected to Facebook and Farmville constantly throughout the day and night, you can send a total of 8 Gifts to the same player in any 24 hour period. This would be very useful if the player on the receiving end were building a Barn or Beehive or whatever, but it sometimes is difficult to remember what each Neighbour is doing at any given moment.
Player can request specific materials for their Building projects but those players, when they RECEIVE the Item they have requested, should not hit the automatic 'thank you gift' button to return the same item to you. This is in fact what occurred, I believe, with my Neighbour who now has sent at least 6 Bottles to me. I am going to put a stop to the endless give and take now. If she was building a Nursery, she surely has all the Bottles SHE needs now, and my Nursery was completed some time ago.
Nails, Bricks and Boards are building materials that are used in ALL construction projects. You therefore can send those safely to almost ANY Neighbour again and again, in the knowledge that they will be useful at some point.
Items that cannot be used usually bring little or no financial return when sold. The excess Thatch, a material that was used to build the Japanese Barn now sits collecting virtual dust in my Gift Box, in the forlorn hope that one day there will be another construction project for a building that requires thatching on the roof.