Bro Suzuki GS 150 i an awesome bike but lacks in some feature:
1. Disk Brakes
2. Alloy rims
3. Fuel and gear identifier on meter.
But Yamaha YBR have all of them also yamaha have a great look, only yamaha does not have is 150cc engine
Which not really matters, if you often goes to long routes then choose GS150 other wise go for YAMAHA
Suzuki GS 150 have new model that do have disk brake and alloy rims but it cost around Rs.158,500/- (without registration)
Don't go for GD110 or 110s as they are not much powerfull and fuel consumption is as same as GS150
Also if you buy GS 150 then get its rear tyre changed as bike is quite heavy and is difficult to make it stop on high speeds due to less road grip.
As far As installment plan is concerned in yamaha case you have to pay the interest whether through bank or through dealer but in case of Suzuki (bank is always an interest game) you can go to any dealer and tell them that you want bike on installment but free of interest.
They will offer you some packages which are without interest in which you will give them some advance and rest will be given in installments which will be without interest.