How to make NPC "sell" outfits

[Alice Lovelin]

I currently have this "Addoner" npc on my server, which allows you to bring him the items you need for addons, or, in the case of the outfits that are store-only in the original Tibia, you can give him "Raid Tokens" from the server events to get the Addons for these outfits. But what if I want to make him also offer the store outfits themselves? I know how to disable them from being unlocked by default, but I don't know how to program the npc to make the exchange.

Here's a sample of part of the NPC's programming in case you need for reference.

I'd love to learn this, thanks in advance.

 local keywordHandler = KeywordHandler:new() 
local npcHandler = NpcHandler:new(keywordHandler) 
NpcSystem.parseParameters(npcHandler)
function onCreatureAppear(cid)            npcHandler:onCreatureAppear(cid)            end 
function onCreatureDisappear(cid)        npcHandler:onCreatureDisappear(cid)            end 
function onCreatureSay(cid, type, msg)    npcHandler:onCreatureSay(cid, type, msg)    end 
function onThink()                        npcHandler:onThink()    end
-- Storage IDs -- 
citizen     = 22001  
hunter        = 22004     
mage        = 22056     
knight        = 22007     
nobleman    = 22009     
summoner    = 22011     
warrior        = 22013     
barbarian    = 22015     
druid        = 22017     
wizard        = 22019     
oriental    = 22021     
pirate        = 22023     
assassin    = 22025     
beggar        = 22027     
shaman        = 22029     
norseman    = 22031     
nightmare    = 22033     
jester        = 22035     
brotherhood    = 22037 
wayfarer = 22039
pumpkin = 22040
yalaharian = 22041
glooth = 22042
rift = 22043
elementalist = 22044
newaddon    = 'Here you are, enjoy your brand new addon!' 
noitems        = 'You do not have all the required items.' 
noitems2    = 'You do not have all the required items or you do not have the first addon, which by the way, is a requirement for this addon.' 
already        = 'It seems you already have this addon, don\'t you try to mock me son!' 
     
  
  
   -- ELEMENTALIST START -- 
function elementalistFirst(cid, message, keywords, parameters, node)
    if(not npcHandler:isFocused(cid)) then 
        return false 
    end
    if isPremium(cid) then 
    addon = getPlayerStorageValue(cid,elementalist) 
    if addon == -1 then 
        if getPlayerItemCount(cid,13940) >= 1 then 
        if doPlayerRemoveItem(cid,13940,1) then 
            selfSay(newaddon, cid) 
              
            doSendMagicEffect(getCreaturePosition(cid), 13) 
            doPlayerAddOutfit(cid, 432, 2) 
            doPlayerAddOutfit(cid, 433, 2) 
            setPlayerStorageValue(cid,elementalist,1) 
        end 
        else 
            selfSay(noitems, cid) 
        end 
    else 
        selfSay(already, cid) 
    end 
    end
end
function elementalistSecond(cid, message, keywords, parameters, node)
    if(not npcHandler:isFocused(cid)) then 
        return false 
    end
    if isPremium(cid) then 
    addon = getPlayerStorageValue(cid,elementalist+1) 
    if addon == -1 then 
        if getPlayerItemCount(cid,13756) >= 1 then 
        if doPlayerRemoveItem(cid,13756,1) then 
            selfSay(newaddon, cid) 
              
            doSendMagicEffect(getCreaturePosition(cid), 13) 
            doPlayerAddOutfit(cid, 432, 1) 
            doPlayerAddOutfit(cid, 433, 1) 
            setPlayerStorageValue(cid,elementalist+1,1) 
        end 
        else 
            selfSay(noitems, cid) 
        end 
    else 
        selfSay(already, cid) 
    end 
    end
end 
-- ELEMENTALIST END --