Is this the same poster under 2 different names?
The amount really won't vary by much. To get a more exact number you would need to provide more information. A lot will depend on taxes, insurance, pmi. You did'nt say what loan program you are wanting to use so I assume FHA. FHA likes to see the house payment at no more than 31% of monthly gross. Which for you would be $2108. Again assuming an FHA loan you will have MIP no matter how much you put down and taxes and insurance-which you have said you don't know how much they are-also have to figure into that payment.
It is possible to go a little higher if your file is strong. You don't mention what is on your credit but I am assuming something is holding your score down in the mid 600's-so that could go either way. Other things they will consider is how long you have been on your jobs/in same line of work. How much reserves will you have left over after paying down payment and settlements costs. Is your down payment your own money or is someone gifting it to you.How much is your rent payment now. They are going to want to see you staying in the same payment range your in now.
So say for example right now you are paying $1200/mo rent, have no reserves and parents are gifting you DP, UW probably won't want to see you going up to a $2500/ mo payment.
On the other hand say now you are paying $2000/mo rent, have all your own DP & settlemens costs, and after all that is paid you will still have $20,000 left in reserves- the UW would probably feel more comfortable approving a $2500 mortgage payment.
