Buying & selling App (95% is completed)

The app is buying and selling app .. where users can post products for sale you can say the projects is 95% completed but is has some issues needs to be fixed (this is the initial bugs ) please read them fully and comeback to me with you questions, cost and time required 1-the app was built 2 years ago .. so now it needs to be updated to the latest android sdk 2-tagging other users in the app by using @username .. it is not working properly 3- cropper integration The photo quality are very bad .. because of the cropper .. so you need to incorporate a cropper into the app .. like instagram .. and make sure the photos quality is top,super clear 4-Sending messages to all users is from the cpanel .. needs to be enhanced. . Now it is accepting only text .. it should accept photos or videos too 5- users now can post only photos ! So if they want only video they can't. . So this has to be edited .. the video is just link from YouTube. . It is already their but when we try to post only video it says choose at least 1 photo 6- the app has hidden slider for the product categories. . Now when we choose a category. . It is nt directing to the required page .. it should 7-add report button to (Review Page) 8- add sold/unsold option .. to mark the product is sold 9- the app shows post filtered by the registered country. so each country shows different posts .. so i need you to make sure the filtering is working across the app including search. 10-suggestion issue. one of the features is sending messages inside the app .. so user should get suggestion for the username once starting to type so the app need to be tested it is free of bugs and fully working