Sophie’s working legs

Sophie is a loving one year old Rottweiler x Mastiff who my ex got as a rescue when she was 5 weeks old (she had already been separated from her mother and had a rough start). After my ex and I broke up he kept her for 3 months then asked me to have her temporarily but ended up refusing to take her back and telling me to re-home her. I got her fixed, registered, vaccinated and microchipped and have loved her with all my heart. It’s been a little tricky as I already had a Rottweiler who’s a handful but I’ve been managing okay. That was until a few weeks ago when I took her to the vets for an injury that happened before she was in my care and unfortunately she needs to have her cranial cruciate ligaments operated on. Basically it means two operations. One for both her back legs. $2000 each.. I’ve got a little savings and with the extra hours I’m working I’ll be able to come up with the 2k for her first surgery but I’m stumped with how I’m going to afford the second and if she only gets one fixed instead of both then it’s back to square one with her in a whole lot of pain and un-able to walk.