Newbie with a few questions on next (first?) steps

[Maya Martin]

I have 1 door that is completely paid off. Its generating about $400 a month cash flow. I really would like to get into buying a few rentals/BRRRR. My current rental is being rented out and needs a few repairs. Wish list includes new bathroom, gutters, garage doors, siding, 1 window, heating system, and back deck. It doesn't 'need all of these right now. House is more than livable as is, just things that need to be done soon. I could mortgage the rental, and fix it up pretty nice. I could also take out a bit for the down payment on the next. I likely will not be able to raise rent that much though. The rental is out of town so it might be difficult to raise rent and keep a good tenant. At the same time, I feel like I should fix it up ahead of time for an exit strategy if the current tenants move out and I can't rent it (IE sell). Question is, do I mortgage it as much as I can without turning it into a negative cash flow, make the repairs on it and call it a day? Should I take money out of it and fix up bare minimum, and dump the rest into the next property and not really worry about the exit strategy on current rental? Do I mortgage at all or do I use the almost $35,000 unsecured LOC (higher interest rate) that I have access to, fix it up, mortgage it at the ARV and go on to the next and pay off unsecured? I am new at this (sort of fell into the rental when a family member passed and willed it to me, with a mortgage at the time) so if there are better options, please feel free to suggest! Thanks in advance!