Essentially once you have paid the full contract balance into the account your contract has ended and the bank will close the account. Investec seems to be the only bank that does allow you to access your funds however FNB/Wesbank does have an option called "Capital Reduction" which essentially...
Based on your current situation, it would be simpler to apply as Self employed.
The bank will only finance you for a year at most due to your contract only being valid for that long. Also due to you not having any payslips, the bank wont have sufficient information to validate your income...