In the current market, it's a little easier for buyers because there is less competition among them. A couple of years ago, the majority of homes in Oakland, Berkeley, Piedmont, San Leandro, Alameda and surrounding areas in the bay area were receiving multiple offers which resulted in almost every property selling for over asking price, with some of the higher end homes selling for as much as $200-300k over asking! Just imagine, some of those properties actually generated as much as 30-40 offers! How would you feel being 1 out of 30? These days there are fewer offers on most properties, which means there's a better chance of yours getting accepted.
So you've been shown a property and you want to submit an offer on it. The first thing your agent needs to do is find out is whether or not there's an offer date or if the offers are being taken "as they come." This will give you an idea of how quickly you need to act. After you determine when you will submit the offer, wait until a couple of days before you submit and have your Realtor ask the other agent how many offers they plan on receiving and how many disclosure packets have been requested on the property. This will give you an idea of the competition you will face, and can help you determine your offer price. For example, if you learn a couple of days before the offer date that there are ten disclosure packets out and the agent expects at least 5 offers, then you may want to consider bidding over the asking price to have a chance of getting it. On the other hand if you find out that the agent is expecting few or no offers then you have a much better chance of getting the property at or below asking price.
In general, buyers are able to ask for a little more leeway with their offers these days. It used to be that buyers who asked for a 30 day escrow were weaker beacuse some buyers were offering to close in two weeks! These days, 30 day escrows are common and shoudn't put you at a disadvantage. The larger the down payment you can provide the better, especially if you have competiton. Make sure your Realtor asks for enough time to remove contingencies, but not too much time. Seven to ten days is a good time frame to ask for while still not delaying things too much. If the property is a fixer or needs any type of significant work, you may need a little extra time to have any and all inspections done before you remove contingencies.
What Realtors who represent sellers are looking for in an offer are: pre-approval letters, good down payment, reasonable contingency and escrow periods, minimum of credits back.