The VA rates are pretty well established by Hud, therefore Lenders are going to be very comparable. You can however buy down the rate, you must however calculate the points and the differance in the amount per month and how long it takes to pay back that point . with the historical low rates it is not wise to pay for points.
closing costs must be paid either by the seller or buyer those can not be added to the loan amount .A professional Realtor representing your interest shoul be able to negotiate that in the contract. I help a lot of Veterns , and in Most cases my clients got a check at closing. There is a lot of talk about Buyers agent and getting representation , the bottom line is A Realtor who does just that and not want to just sell you a home but provide you with accurate information an the market and knowledge about appreciation and the best way to get into a home before you buy. That is why our clients of the past 15 years have not called me with having to file foreclosure or even the threat of losing their home . because they were represented properly and not just sold. We have built our Buisness on Honesty and Integrity.