There are several options here:
1: first : don't re-invent the wheel and don't make enemies... Go to the realtor (even if you have a trusted realtor): and ask the listing agent questions: (i'm sure he wants to sell it... as he has not made any money on it for 1 year and has been answering questions from people like you all this time).
so go to him and ask him: what is the seller's bottom line?
Can you represent me on the sale of this home and at what price?
What if you go to the seller and ask them what they would want for it CASH and i pay you on the side... (pros and cons to this).
What is important to the seller? (this way you can craft a plan of action that is solving the seller's problem).
Would the seller want to partner with me : where I fix it and sell it and we split profits?
If the realtor is unwilling:
Go to the seller and ask him to buy it from him
All the same questions above straight to the seller
Send her a letter by mail and explain your intentions
Get financing from a Hard money lender: offer cash and refinance it into a regular loan.
** and yes: I don't know how you are arriving at 50k
But go see it: based on comparable sales arrive at an ARV (after repair value): then get the estimated rehab cost from a reliable contractor:
Then get the ARV $: times 65% : that will give you X: minus repair cost : and that will equal your offer price
For example: ARV is $100k : times 65% : or 65k minus 20k in renovations:
so your offer will be: $45k
You can't lose with this formula.
Make sure you do your due diligence.
Realtors will be your allies not your enemies :)
(and you didn't want realtors responding to this right... ) ;)
Good luck:
Let me know if you want me to make the call for you (no joke)