Regarding the eligibility of back Federal taxes to be discharged in a ch7 bankruptcy, yes they can ... if certain requirements are met. Google the subject and you will see the specific requirements.
Buyback of an asset - the trustee will set value for each asset taken for disposition. Before those assets are sold, the petitioner will have a short time period during which the asset may be bought back or "redeemed".
A ch 7 discharge is going to have a significant impact on your credit scores and your ability to secure new credit. No way around that. Worry about rebuilding once your discharge is complete. Until then, there is a lot written on the subject of credit rebuilding here so just read up and figure out a plan that makes sense for your personal circumstances. Many of use here have travelled that road as we stand as proof that it can be done and often quicker than one would think possible.
All the best going forward.
