Looking on the internet deeply has found these results:

at the client’s disposal is the most popular phrase on the web.

at client’s disposal 12,140 results on the web	at the client’s disposal 126,300 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
An attorney who thinks his client's innocent. My client's already admitted... My client's privacy is nonnegotiable. Satisfying your client's every need. Application to exclude my client's interview. My client's still facing charges. My client's legal status in Germany is insecure.	Seems particularly in the client's interest. Regrettably, the next target been moved up at the client's request. Did something happen at the client's apartment? Cassie, if you look at the client and see a man with an Uzi, that's not exactly handling it. The fact that the retail trade monopoly alone has the right to deal with private imports at the client's request is regarded by the Commission as an obstacle to trade, which should be assessed in the light of Articles 28 EC and 30 EC. This all started at the client's apartment. However, these agencies and organisations do not provide direct supervision of their employees at the clients' work sites. The client's already seen it.

at client’s disposal

12,140 results on the web

at the client’s disposal

126,300 results on the web

More popular!

Seems particularly in the client's interest.
Regrettably, the next target been moved up at the client's request.
Did something happen at the client's apartment?
Cassie, if you look at the client and see a man with an Uzi, that's not exactly handling it.
The fact that the retail trade monopoly alone has the right to deal with private imports at the client's request is regarded by the Commission as an obstacle to trade, which should be assessed in the light of Articles 28 EC and 30 EC.
This all started at the client's apartment.
However, these agencies and organisations do not provide direct supervision of their employees at the clients' work sites.
The client's already seen it.