Dear Gurtam development team
In our country, customers pay for Units per year and as we discussed with Gurtam support team there is no possibility to block Units in Wialon system. Gurtam support team offered us some tricks but none of those ways can exactly do what we need. Let me to explain our situation understanding the exact problem.
Consider a customer (mostly a dealer) ask you for an account of 30 Units for a year at the beginning of 2016 and you charge them. Then, after 6 month they ask you to increase their Units limits to 50. In CMS you have only 2 way to block a customer, block by days and by balance. If you want to use block by days for such a customer, so, when would be the expiration date? end of 2016? end of June 2017? you see, it doesn't work. Another way (Gurtam support offered us) is to use block by days and block by balance together. The prospect is to consider a service charge for each Unit per day/month and set the system to withdraw this service charge from account balance. for example if you consider 10 unit of service charge monthly for each Unit then for first 30 Units you should add 30(Units)*12(month)*10=3600 and for next 20 units 20(Units)*12(month)*10=2400 and total balance for 50 units will be 3600+2400=6000. At the end of 2016 the balance will be 1200=6000-(30*12*10)-(20*6*10). As the customer should pay for next year (2017) so the block balance should be 1200+ 3600(for 30 units for 2017)=4800 and if you set this you can control the customer, if they pay you will add 3600 balance to their account and if they don't pay system will block them and you will decide to remove their Units or... based on your company policy.
This is our situation and the way explained is the way Gurtam support team offered us. But, there is some problems. When we are talking bout dealers we can't control when they add their Units. We offer an account to dealers and limit number of Units in their account. We can't control when they will add Units and the way Gurtam support team offered will work only if a dealer add all 30 Units on 1st January of 2016 and all another 20 Units on 1st July of 2016. Think about such a situation that they add 5, 2, 14, ... Units within 2-3 month! it's impossible to calculate when you should block the customer.
I'm thinking about a new function in CMS to block Accounts. It can be a new Block way in Restriction tab or a new item in Services tab of Account Properties. What we except of this new function is that to withdraw balance (the Balance Wialon has now or any other kind of balance that can be add as new feature) a specific amount each day. Let's call this specific amount of balance the System Service Charge. So, if you set this System Service Charge equal to customer's units then you will be able to control dealers. With such a function you can set Wialon to withdraw i.e 50 (for 50 Units) units of balance each day. then if the customer (dealer) wants to increase units to 70 Units, the only thing you should do it is to set System Service Charge to 70. If i want to explain difference between what Gurtam support team offered us and what we need i should say that their suggestion works based on actual number of Units in Accounts but we need it to work based on maximum number of Units in Accounts.
I'm sure it will be very helpful to control dealers or customers who want to add their devices himself (big companies with IT department who is responsible about such cases) even they pay monthly not yearly.
Please inform me about possibility of adding this function to Wialon or any trick/way can help us.