I'm being sued for Buyers Remorse?

I live in Michigan and purchased a used/damaged Ohio car with a salvage title for $1,200 and shipped it back to Michigan to fix but then decided to sell it for $1,500 in Michigan because I do not have time to fix it anymore. I did not title the car in my name because I only had it for 2 weeks and the DMV is backed up due to COVID-19. 

Kim(the buyer) signed a bill of sale for me saying "Eddy(me) is not reliable anymore, Kim acknowledges it has a salvage Ohio title, understood vehicle can be fixed or used for parts, no refunds or returns, sale is final and Kim(her) is taking full responsibility for this purchase". 

I did not force her to buy it. The vehicle sells for $3,700 on craigslist and has a KBB value of $4,000. Her mechanic & mother checked it out for her before buying. 

Her mechanic even told her it has to be fixed first then re-titled at the DMV to make it a Michigan rebuilt title. She replied to him "whatever".

Two weeks later after she fixed it she decided not to title the car and do the inspection because to make it a rebuilt Michigan title it will cost $200 for the state inspection and plus 6% of $1,500 = $90 costing her $290 total in DMV/titling fees. 

Instead now she has buyers remorse and told me she wants a refund or will sue me because the next available appointment at the DMV is 5 months from now due to COVID-19. That is not my fault. She knew what she was buying. Am I still responsible just because I did not title it in my name? Will I lose in court?