Unfortunately, BOFA has stopped foreclosing on homes in many areas due to botched paperwork. It seems that the company among others signed off on foreclosures without reading the paperwork and checking to see if the homeowner was in fact behind on their mortgage. Add that to the fact that the national average time to foreclose on a house right now is over 400 days. So, you may want to ask the bank if you can stay without making a mortgage payment and keep the house "lived in" to keep the house from growning with mildew and tall grass (although it's probably cold there now). A bank loses more if you move out than if you stay there and not pay the mortgage.
I don't know what to tell you about the IRS Tax Lien as I don't have enough info from you to know where it came from. If it's a property tax lien for non-payment of property taxes, it stays on there until you pay it off or 10 years lapses. Be careful with these as they can come after your paycheck or worse. If you show minimum monthly payments, it may help stave them off and not seek legal assault on your life.
You may want to consider selling the home for at least what you owe, renting it out or doing an owner finance deal where the buyer doesn't have to go through credit checks and you get the money due to the bank from the buyer. Give them 3 years to clean their credit to buy.
If you have a government loan, FHA or VA, someone may be able to assume your loan.
You may ask a Realtor to help you with a short sale (although Wells Fargo is refusing to extend short sale contracts).
As a co-signor, if it is showing up on yoru credit report, it is counting towards your debt to income ratio. to be sre you ned to meet with a local and trusted mortgage broker, they can prequailify you at no cost, look at your creidt report, credit score and financials and let you know what mortgage programs you may quailify for.