Never start work on a friday, especially when the person
a) comes in at 10 am and leaves sharp at 5 pm, even when the office hours are 9 to 5, and you say the job is critical. Never mind the loss to the company when the website is down for the weekend. It is weekend in India, but still 3/4ths of a day is left in US/Europe
b) doesn't work unless you sit with him, has to be spoonfed in such a way that if you were doing the work yourself, you would be doing it faster, but he has three-times more 'experience' than you
d) with his 'experience' asks 'how?' when another guy, a newbie, does it without thinking
e) is in the payroll of a company but does freelance work at company hours
f) everybody else cribs about him to you, even your boss' minion
Start the work under such conditions, only if you don't have a personal life and/or can't afford to let the company website go down for even a minute AND you are willing to write off your weekend for this.