REA asking me to sign before making an offer.

I told them I'd have my conveyancer look at the contract first. If it comes back a-ok, should I make the offer written/verbally and ask them to take it to the seller, or should I sign what they want me to whilst they take the offer? (context: Vic, unit that has been on the market for 2 months. Inspection had no one else there.)

Update: I've forwarded on the contract to my conveyancer. I'll update again if anything spicy is found or if it was actually fine and I purchased, otherwise just assume that it wasn't worth it in the end.