Butt/back lump removal/advice

[LDatemasch]

My guinea pig Peach (2 years old, female) recently developed a lump on her back/booty area maybe 2 weeks ago. I, of course, took her to the vet, though she seemed (and continues to seem) absolutely fine - eating, drinking, zooming, etc.
The vet first attempted to drain the lump, in case it was an abcess, but she said that nothing came out. So they then took a sample to send for lab tests. A few days ago I got the call that the lump was not cancer and also wasn't infected. They told me I could basically just leave it alone unless I wanted it removed for cosmetic reasons.
Yesterday, I checked the lump and THERE IS A HALF INCH DIAMETER ROUND HOLE IN IT. It doesn't look like there's any blood or pus, but the skin is a bit red around the edges of the circle... inside is like white/gray and just looks like fatty cells? This seemed to line up with what I would expect from inside a lipoma.
It was Sunday so the vet was closed, so I boiled 8 oz of water and put a tsp of salt in the water and let it cool. Then my fiance and I flushed the hole/wound with the saline water. I was hoping to prevent infection.
Today I got in contact with the vet and they said antibiotics won't do any good, and now it needs surgically removed. They gave me contacts to 2 exotic vets that do surgeries. I'm just wondering if anyone has any idea what this will cost? What can I do to keep the wound from getting infected in the mean time? I'm completely at a loss. Please advise me

Also, as I said, she is still eating, drinking, and wheeking for veggies as of this morning.

 

[Siikibam]

Hi there. I’m afraid I have no experience with lumps etc. You’re better off contacting the vets to ask them how much it may cost. I’m not sure where you’re located by I know the vet fees in Canada and the US can be much higher than here in U.K. I’ll tag @Wiebke @PigglePuggle @Piggies&buns

 

[Freela]

One of my pigs, Linney, had a similar lump... in her case it ended up being a kind of cyst. The vet did a needle biopsy and excised some of the contents. After that, the skin overlying the cyst seemed to die off so that she had a bit of the cyst capsule protruding through the skin... at that point we decided to remove the lump in its entirety. It was a pretty quick surgery under general anesthesia, she got stitched back up (the shaving/stitching made it look much worse that what it was!) and she never had another problem with it.

Cost is really going to vary vet to vet, so it's worth getting a couple of opinions. I'm in Ontario, Canada, as I recall Linney's surgery was a couple hundred dollars, plus followup antibiotics and the initial 60 dollar consult appointment, but like I said, it is going to vary dramatically for every vet.