There are more options, but this is sufficient to answer your question. 

Some will be ok in 2nd position and some will not and force you to refinance out the first - but those are options that are probably cheaper than credit cards 

Have you also looked into other funding options?

Hi to everyone,I would like to ask that ,my banks in my country (Greece) are unable to provide refinance options for the BRRRR method (Buy, Rehab, Rent, Refinance, Repeat), what alternative realistic strategies can I consider for implementing this investment approach?

There are so many options for LVP now, from lower priced to higher.

If I wasn't able to get the cash together, using a private lender would've been a good option.

Master Lease with Option. 

My lender is suggesting me to buy property under my name and then transfer it to LLC later as there are not many financing options available for LLC.

I think we have the option of taking out a heloc  and begin to invest elsewhere.The other idea , that I was thinking is paying off our primary residence which we owe 425k.

Your suggestion to list on open market likely is the best option for the OP.