Unicenta java pos opensource updates

hello , i have my own unicenta(opensource java pos app ) customized version for my clients working on just MySQL database .. now im thinking of add some developments of the system these updates is : 1. online sync for last online database of items ( so every time client do a sync his new products posted to a web API , then he will download the all new items from the cloud ( i can do tha api online but i need your help in the unicneta section from 0 to 100 ) 2. offers panel this panel will have three types of time based offers and the customer can show the current offers and modify , extend duration of the offer , delete it a. offer based on item count in one invoice , so if the customer bought 3 items for example this will change the line total price to certain offered price and store the sell price ass discounted on the database b. buy 2 get 1 free theme ( if customer buy x items the next n items from the same product will be free ). c. buy +100$ get 10% discount ( if customer invoice exceeds x $ a special discount of N% will be added to the invoice ). please send me a price offer of every details from above separately and the delivery time of the projec