More expensive house: Add money to mortgage?

dutchcloggie

Hello,

I am moving to a new city where houses are more expensive than my current one. 
My house is sold for £226,000. I have a mortgage of £85,000. My new budget needs to be around £250,000 - £260,000.

Now I have done a new mortgage in principle with my current lender and they will lend me up to £160,000. I don't need that much of course so I am looking at around £110,000 - £120,00. This would be made up from £85,000 of my current mortgage at 3.3%, which I fixed for 2 years in January, and then borrowing an additional £20,000 - £30,000 for a new fixed rate.

I am confused about calculating my monthly payments for al this. I currently pay £520 per month for the £85,000.  How will I know if I can actually afford the additional mortgage payments without applying for the mortgage properly? I mean, just because the bank says they will lend me £160,000 does not mean I will feel the monthly payments are affordable.  

I can find this out by applying for a mortgage. But I wont be able to do that until I find a house I want to buy. But until I know how much it will cost, I don't know how much I can increase my budget by....

Sorry if I am being stupid. I have dyscalculia and I cannot wrap my head around the calculations and how to do them. Thanks for any gentle help :-) 

ACG

Have a play around with this. https://www.bbc.co.uk/homes/property/mortgagecalculator.shtml

£30,000 over 20 years at 4.5% is around £170 per month. So your new payment if you did £30k over 20 years at 4.5% would be £170 + £520 = £690 per month. 

dutchcloggie

Ah. That looks bloody simple. I hate that I cannot think of that myself. Thanks!