Do I have to sell my house to afford buying?renovating a new house?

[Rosalita Smith]

So I have my house that refinanced in 2020 for a 15yr 2.5% rate and we have about 56k equity. Purchased at 211k . We have an opportunity coming up from a family member who is willing to sell us my childhood home for what they got it for (240k) and the comps in that neighborhood are 600k+. Ideally we would love to live in my childhood home. I will have some inheritance coming in soon (About 50k). The childhood home needs quite a bit of work but I couldn't really guess how much. I'd really hate to sell my current home with such a good rate. And I would love some passive income or at least someone to pay my mortgage until we can pay it off maybe. Is the only way to pay for a Reno for my childhood home to sell my current home or is there a method I'm not familiar with that I can use my current homes value to help me out?? We don't have a ton of income. There isn't a lot of capital besides the small inheritance I have coming. The current comps in my current neighborhood are like 350-400k now. This website has been so enlightening to me but I am super new to this. TIA!