I think Shane is correct. Most likely you need a FHA 203k Loan. These can be costly and time consuming. It depends on whether you need a FULL 203k Loan or a Streamlined 203k Loan. The difference is the amount you are borrowing to make repairs.
FHA wants to make sure they lend you money on a home that is worth lending money on-- and if it needs significant repairs, they want you to hire a contractor to make the repairs immediately so that they are loaning money on a repaired home. So, based on your loan amount of $105,000 -- and your purchase price of 90,100 -- that leaves $14,900 for repairs -- assuming the seller will also pay for your closing costs. As long as the home needs $14,900 or less for repairs you can afford the home.
The offer will be $105,000 with $14,900 to be given back to you at closin
g -- to be written as a check to your contractor -- for the repairs. This will NET THE SELLER $90,100-- their asking price.
Now, you can always offer LESS than $90,100 and your REALTOR can help you know what to offer to the seller. Every $1 can be added to the amount you use to make repairs.
I recently had a client purchase a property for about $130,000 with an additional $140,000 for repairs. His loan was for $270,000. And he was able to get an appraisal after the home repairs were finished and it was over $350,000!