I would really look for an agent that had experience helping many first time buyers. I usually coach first time buyers on all cost involved in the purchase and never borrow too much unless you have a tax shelter opportunity that is big enough and worth to do a big mortgage. Most buyers will sell their home in 5-7 years (by statistics), therefore be conservative the first time is always clever. Next, if you are borrowing, run by a lender to see all cost involved be sure to add property tax and maintenance cost so you are covered in all angles. The rule of thumb usually is that spend 1/3 of your net salary in housing, 1/3 on savings and 1/3 on food and expenditures on vacation and on quality of a lifestyle. If your rental is the same as mortage, why not own a home earlier and earn equity sooner.Hope that helps!
Rather than walking away, best way is to call your lender to discuss and most lenders these days will work with you on a program that fits you. It all depends how much you owe, I had an experience that I helped someone to sell their homes which turned out to be "unnecessary for a short sale", talk to a short sale listing agent is another options, you should see a lot of options out there, you are not alone, many are with you these days.
Contact also one of the title representative to reflect changes on public record including accessors record.
There are a lot of difficulty in selling a home by seller themselves as there is a lot of emotionals involved. Using a third experienced party will prevent such kind of emotional judgement as a result. The buffer can set a accurate price point, negotiate at a fair neutral standpoint and can do all the hard work of showing and telling for seller. Most important, they are paid so sellers will not be bothered by all phone calls or any comments that may be irritating when buyers start bargain left and right. The correct paperwork will also protect the seller from any liability issues in real estate law.
Most professional agents will do a CMA - comparison market analysis. The data drawn for this conclusion must be within past 3 months so it can be recent data and it is similar to the size of your home and finally, an agent has to determine the price after seeing the interior of the home and using their expertise, they should be able to tell the price quickly.
When you sell your home, you can disclose all sq ft by seller, it is up to buyer to verify with city. You can also hire a professional to do a floor plan to indicate this living space that is usable, as of final approval, it is up to city for permission in requirement and standard to make it public on the assessors' record.
If you need to buy, you need to, most important I feel in the past from clients comment was that finding a good agent is the most difficult as to find an honest agent and will focus on customer needs and not their commission check. As we all know; if we serve them right, we got our fair reward.