What if I accept client offer, start working and add manual hours?

[contactsapphire]

Hello Team,

I have a awkward situation wherein I have an offer for hourly, I know what I am doing, even client has confrim and awarded, but before we begin I want to talk to the client for trust.

(A) If I accept the offer and what if client refuse to pay for work.

(B) I do not accept offer and I will loose the contract since client is thinking I have accepted and begin work and will show once the client come back from a Radio Silence.

(B) What if client never show off for months at what point we have to stop?

(C) What if client dispute without any reason after coming back from months of radio silence?

I do not want to loose the contract since we can do it and it is equally important for me to have this contract like others. We are top rated on upwork, and want to continue this status, what if client do a dispute without any reason. 

Trust is only the barrior since we have not done any one on one e-meet with the client, we have just done text conversation. 

Please help me to make a decision whether to accept offer and start working or let the offer be like that until clients come back.

Regards