The foreclosure agent does BPOs everyday. Its a report that gives a value, like an appraisel. They look at whats sold, whats for sell, and gives a price. They are not going to inflate the price to try and secure a listing. They are not going to pressure you to get the listing. You will have paid for their service and thats it. If you choose to use that Realtor in the future, thats fine, but you won't be hounded to do so.

whether or not the agent will do an analysis for you or not is up to them. Any Realtor that does an analysis for you will do it in hopes of earning your listing in the future.

While it's true:"Realtors have a stronger sense of the 'people' side of the equation...i.e. what people in today's market are paying and would be willing to pay for your property."
....a low appraisal can certainly kill a deal. You might be OK since you're willing to bring money to the table.. but even then, the Banks are getting weird about ANY hiccupsin the Loan process.

Either get a Realtor to do a SOLD comp analysis, or get the Appraisal so you know where you stand.

For a cheaper appraisal, you can try automated valuation model (AVM). Before the real estate market decline, AVM has been widely accepted instead of a appraiser going out to the properties. It costs $20-$30 and the result is typically close to an actual appraisal. When I was in the mortgage business, I used AVM for clients that were uncertain the worth of their homes and didn't want to spend hundreds of dollars on appraisals.

It's okay to appraise your house or any other property even you have no intentions to sell it. This is to provide you a report that how mush do your property increase or decrease in value.