You could go with a generator, but investigate one or more UPS systems and see how far you can get without a huge investment.
Even if you go with a generator later, you will want to keep the UPS systems to cover the startup gap :-).
I like the APC 1500;
https://www.amazon.com/APC-Back-UPS-Battery-Protector-BR1500G/dp/B003Y24DEU/
[I have five APC 1500s, a 14kw Kohler generator, enough solar to cover my electrical bill, and a Eaton 15kw whole house UPS]