Monthly payments to determine affordability ususally include PITI and HOA: principle, interest, taxes, insurance, and HOA dues. Since this home does not have an HOA nor Mello Roos taxes, it is fairly straightforward to figure out your monthly payments. The key will be the type of loan your qualify for or choose.
There are many loan officers and real estate agents in this business. With an important purchase like a home, you should interview several loan officers and agents. This little bit of extra work in the beginning will make a huge difference at the end.
Ask how many years they've been in the business full time, how many loans or homes do they do per year, do they have an area of specialization, do they have past clients you can talk to etc.
The good ones will help you make informed decisions by answering all your questions, or telling you about things you might not know to ask. They should look out for your best interest, and never pressure you into something. And even though there is a mountain of paperwork, buying a house can actually be fun when you have honest and competent people on your side.