The number of neighbors you can visit a day who you can collect items from and help depends on your reputation level. Starting from the first level, you can visit 4 neighbors a day and you can sponsor them once every 24 hours. You can increase your reputation level to get the opportunity to visit more neighbors by helping them. Each level up in your reputation adds one neighbor to the number of friends you can visit. At present, level 20 is the maximum reputation level.