Vtiger intergration

We currently have a system, which is a very small CRM, but its main purpose is to produce ratios from activities people achieve. So the system we have allows sales agents to go to their activity page select the client, select the type of activity, date time and if complete. this will then be entered into a activity list. VERY SIMPLE! The interesting part is that each activity has an allowed time and from this we are able to produce reports and ratios. One of the key things of our current system is that once an activity is completed and screen appears with possible out comes. basically displaying other activity which could be a result of the first one. Call back on X date Schedule a meeting Was a sale made. Another part we need is commission. Vtiger can already process commission and sales. although I would like this streamlined abit more. The other problem is the commission processing. ideally I would need a model for the accounts team to view sales and issues the commission for the relevent person. This however has another problem as some users have bespoke commission and not the normal product commission, also managers of that user could get commission. I would love to know your thoughts and suggestions on this. I have developed our old system in house but are on too many projects to do this so we are looking for someone, professional, sticks to budgets, on time and for future development of the same system. I shall only allow access to our current system should I think you are able to complete the job. I regularly give outsource jobs, and have been ripped off before, so I will only talk to professional people. But I'm will to give anyone a chance whether they are a single person working alone or a company, I just want profesionalism